Diagnostic accuracy of the Thessaly test, standardised clinical history and other clinical examination tests (Apley's, McMurray's and joint line tenderness) for meniscal tears in comparison with magnetic resonance imaging diagnosis. GRADE: assessing the quality of evidence for diagnostic recommendations Interrater reliability in assessing quality of diagnostic accuracy studies using the QUADAS tool. A preliminary assessment. Do you have to re-examine to reconsider your diagnosis? Checklists and cardiac exam Rapid critical appraisal of randomized controlled trials (RCTs): an essential skill for evidence-based practice (EBP). When Is Measuring Sensitivity and Specificity Sufficient To Evaluate a Diagnostic Test, and When Do We Need Randomized Trials? Academic calculations versus clinical judgments: practicing physicians' use of quantitative measures of test accuracy. How to diagnose spondyloarthritis early? Accuracy of peripheral enthesitis detection by power Doppler ultrasonography Distinguishing benign and malignant pelvic masses: the value of different diagnostic methods in everyday clinical practice. Reliability and Diagnostic Accuracy of the Clinical Examination and Patient Self-Report Measures for Cervical Radiculopathy Non-acute abdominal complaints in general practice: diagnostic value of signs and symptoms. Payment to healthcare professionals for patient recruitment to trials: systematic review and qualitative study. Diagnostic accuracy and association to disability of clinical test findings associated with patellofemoral pain syndrome. The continuing unethical conduct of underpowered clinical trials. How to deal with double partial verification when evaluating two index tests in relation to a reference test? The Value of Medical History and Physical Examination in Diagnosing Sacroiliac Joint Pain Computed critiquing integrated into daily clinical practice affects physicians' behavior--a randomized clinical trial with AsthmaCritic. Clinical predictors of a positive response to guided diagnostic block into the subacromial bursa. Systematic Reviews of Diagnostic Test Accuracy Comparison of Trained Clinician Ratings with Expert Ratings of Aspiration on Videofluoroscopic Images from a Randomized Clinical Trial
BACKGROUND Reliable non-invasive diagnosis of meniscal tears is difficult . Magnetic resonance imaging ( MRI ) is often used but is expensive and incidental findings are problematic . There are a number of physical examination tests for the diagnosis of meniscal tears that are simple , cheap and non-invasive . OBJECTIVES To determine the diagnostic accuracy of the Thessaly test and to determine if the Thessaly test ( alone or in combination with other physical tests ) can obviate the need for further investigation by MRI or arthroscopy for patients with a suspected meniscal tear . DESIGN Single-centre prospect i ve diagnostic accuracy study . SETTING Although the study was performed in a secondary care setting , it was design ed to replicate the results that would have been achieved in a primary care setting . PARTICIPANTS Two cohorts of patients were recruited : patients with knee pathology ( n = 292 ) and a control cohort with no knee pathology ( n = 75 ) . MAIN OUTCOME MEASURES Sensitivity , specificity and diagnostic accuracy of the Thessaly test  in determining the presence of meniscal tears . METHODS Participants were assessed by both a primary care clinician and a musculoskeletal clinician . Both clinicians performed the Thessaly test , McMurray 's test , Apley 's test  , joint line tenderness test and took a st and ardised clinical history from the patient . RESULTS The Thessaly test had a sensitivity of 0.66 , a specificity of 0.39 and a diagnostic accuracy of 54 % when utilised by primary care clinicians . This compared with a sensitivity of 0.62 , a specificity of 0.55 and diagnostic accuracy of 59 % when used by musculoskeletal clinicians . The diagnostics accuracy of the other tests when used by primary care clinicians was 54 % for McMurray 's test , 53 % for Apley 's test , 54 % for the joint line tenderness test and 55 % for clinical history . For primary care clinicians , age and past history of osteoarthritis were both significant predictors of MRI diagnosis of meniscal tears . For musculoskeletal clinicians age and a positive diagnosis of meniscal tears on clinical history taking were significant predictors of MRI diagnosis . No physical tests were significant predictors of MRI diagnosis in our multivariate models . The specificity of MRI diagnosis was tested in subgroup of patients who went on to have a knee arthroscopy and was found to be low [ 0.53 ( 95 % confidence interval 0.28 to 0.77 ) ] , although the sensitivity was 1.0 . CONCLUSIONS The Thessaly test was no better at diagnosing meniscal tears than other established physical tests . The sensitivity , specificity and diagnostic accuracy of all physical tests was too low to be of routine clinical value as an alternative to MRI . Caution needs to be exercised in the indiscriminate use of MRI scanning in the identification of meniscal tears in the diagnosis of the painful knee , due to the low specificity seen in the presence of concomitant knee pathology . Further research is required to determine the true diagnostic accuracy and cost-effectiveness of MRI for the detection of meniscal tears . TRIAL REGISTRATION Current Controlled Trial IS RCT N43527822 . FUNDING The National Institute for Health Research Health Technology Assessment programme Making a diagnosis is the bread and butter of clinical practice , but in light of the number of tests now available to clinician , diagnosing illness has become a complicated process . Guidelines for making an evidence -based diagnosis abound , but those making recommendations about diagnostic tests or test strategies must realize that clinicians require support to make diagnostic decisions that they can easily implement in daily practice . The Grading of Recommendations Assessment , Development and Evaluation ( GRADE ) Working Group has developed a rigorous , transparent , and increasingly adopted approach for grading the quality of research evidence and strength of recommendations to guide clinical practice . This editorial summarizes GRADE 's process for developing recommendations for tests ( 1 ) . Clinicians are trained to use tests for screening and diagnosis ; identifying physiologic derangements ; establishing a prognosis ; and monitoring illness and treatment response by assessing signs and symptoms , imaging , biochemistry , pathology , and psychological testing techniques ( 2 ) . Sensitivity , specificity , positive predictive value , likelihood ratios , and diagnostic odds ratios are among the challenging terms that diagnostic studies typically deliver to clinicians , and all have to do with diagnostic accuracy . Not only do clinicians have difficulties remembering the definitions and calculations for these terms , application of the concepts to individual patients is often complicated . Many clinicians order a test despite uncertainty about how to interpret the result , and they also contribute to testing errors by incorrectly ordering tests ( 3 , 4 ) . GRADE 's framework for developing recommendations for diagnostic management studies is based on what is needed for practical clinical applicationthat is , how to weigh the benefits and harms of ordering and using a diagnostic test in caring for patients ( 1 ) . The approach begins with specifying the PICO : the relevant population ( P ) , diagnostic intervention or test ( I ) ( including its purpose , such as triage , replacement , or an add-on test ) , comparison test ( C ) , and patient-important outcomes ( O ) related to the use of a test for a focused clinical question . If a test fails to improve patient-important outcomes , there is no reason to use it , whatever its accuracy . For example , the results of genetic testing for Huntington chorea , an untreatable condition , may provide either welcome reassurance that a patient will not have the condition or the ability to plan for his future knowing that he will sadly fall victim ( 1 ) . Here , the ability to plan is analogous to an effective treatment , and the benefits of planning need to be balanced against the downsides of receiving an early diagnosis ( 5 - 7 ) . The best evidence of test performance comes from large r and omized trials of diagnostic strategies that directly measure patient-important outcomes ( 1 ) . However , these trials are few and far between : An informal review of the Cochrane data base of r and omized trials revealed < 100 such studies . Therefore , most recommendations about diagnostic testing are based on an implicit 2-step process of how the accuracy of a test indirectly changes patient-important outcomes . In the first step , a diagnostic-test accuracy study ( Figure ) , patients may receive both a new test and a reference test ( i.e. , the best available method for detecting the target condition ) . Investigators can then calculate the accuracy of the test compared with the reference test ( first step ) . In the second step , judgments about the patient importance of test accuracy are based on the consequences of being correctly or incorrectly classified as having or not having the disease . These include the benefits and harms of receiving treatment or follow-up tests for those correctly classified as having the disease , reassurance or receipt of other follow-up tests for those correctly classified as not having the disease , receipt of unnecessary treatment or additional tests for those incorrectly classified as having the disease , delayed or no treatment for those incorrectly classified as not having the disease , and any adverse effects of the diagnostic test ( e.g. , from invasive tests ) . Those making recommendations about diagnostic tests must then compare patient-important outcomes ( and costs ) in all patients receiving the new test with all patients receiving the old , or comparator , test . For the first step ( i.e. , assessing test accuracy ) , there are well-described method ological criteria for assessing risk for bias in an estimate of test accuracy , ideally based on a systematic review of relevant studies . For instance , studies of diagnostic test accuracy with a low risk for bias enroll consecutive patients for whom there is legitimate diagnostic uncertaintythat is , the type of patients to whom clinicians would apply the test in the course of regular clinical practice . If studies fail this criterion ( e.g. , only enroll patients with severe disease and healthy controls ) , the apparent accuracy of a test is likely to be misleadingly high ( 8 , 9 ) . The second step shown in the Figure is , in most situations , based on judgments of test accuracy as a surrogate for patient-important outcomes . The key issue about these judgments is that they should be made transparent to those using the recommendations . For example , in the diagnosis of suspected acute urolithiasis , well- design ed studies demonstrate fewer false-negative results with noncontrast helical computed tomography ( CT ) than with intravenous pyelography ( IVP ) ( 10 ) . However , those ureteric stones that CT detects but IVP misses are smaller and therefore are more likely to spontaneously pass . Before r and omized trials evaluating outcomes in patients treated for smaller stones , evidence from observational studies was of lower quality . Thus , it remained uncertain how patients were affected by missed cases and follow-up of incidental findings unrelated to renal calculi with CT .  Recommendations about using one test ( IVP ) over the other ( helical CT ) were based on judgments of how the cases that were detected or missed would fare with or without treatment ( 11 ) . These judgments were likely to be based on indirect evidence and would be less certain than judgments based on direct evidence from a r and omized trial comparing the 2 tests . The GRADE approach requires making these judgments about the relation between accuracy and patient-important outcomes transparent . The example of IVP versus helical CT for patients with suspected acute shows exemplifies how the quality of evidence for an accurate test would be down grade d because of the lack of direct evidence on patient-important outcomes . Uncertainty about patient-important consequences and associated uncertainty about benefits and harms would probably have result ed in weak GRADE recommendations about the use of IVP compared with helical CT . Those making recommendations using the GRADE approach should also explicitly consider judgments and evidence about the values and preferences that patients attach to important consequences , as described more fully elsewhere ( 1 ) . Acknowledgments : This work was partially funded by a The human factor , mobility and Marie Curie Actions Scientist Reintegration European Commission Grant ( IGR 42192 ) GRADE to Dr. Schnemann RATIONALE AND OBJECTIVES Quality Assessment of Diagnostic Accuracy Studies ( QUADAS ) is a new tool to measure the method ological quality of diagnostic accuracy studies in systematic review s. We used data from a systematic review of magnetic resonance spectroscopy ( MRS ) in the characterization of suspected brain tumors to provide a preliminary evaluation of the inter-rater reliability of QUADAS . MATERIAL S AND METHODS A structured literature search identified 19 diagnostic accuracy studies . These publications were distributed r and omly to primary and secondary review ers for dual independent assessment . Review ers recorded method ological quality by using QUADAS on a custom- design ed spreadsheet . We calculated correlation , percentage of agreement , and kappa statistic to assess inter-rater reliability . RESULTS Most studies in our review were judged to have used an accurate reference st and ard . Conversely , the MRS literature frequently failed to specify the length of time between index and reference tests or that the clinicians were unaware of the index test findings when reporting the reference st and ard . There was good correlation ( rho = 0.78 ) between review ers in assessment of the overall number of quality criteria met . However , mean agreement for individual QUADAS questions was only fair ( kappa = 0.22 ) and ranged from no agreement beyond chance ( kappa < 0 ) to moderate agreement ( kappa = 0.58 ) . CONCLUSION Inter-rater reliability in our study was relatively low . Nevertheless , we believe that QUADAS potentially is a useful tool for highlighting the strengths and weaknesses of existing diagnostic accuracy studies . Low reliability suggests that different review ers will reach different conclusions if QUADAS is used to exclude " low- quality " articles from meta-analyses . We discuss methods for improving the validity and reliability of QUADAS Background Few studies have investigated whether clinicians can use checklists to verify their diagnostic decisions . Checklists may improve accuracy by prompting clinicians to reconsider or recollect information but might impair decision making by adding to clinicians ’ cognitive load . This study assessed whether checklists improve cardiac exam diagnostic accuracy , and whether this benefit is dependent on collecting additional information . Methods 191 internal medicine residents examined a cardiopulmonary simulator .  They provided a diagnosis , subjective rating of certainty , and key findings before and after using a checklist .  Residents were r and omised ; half were allowed access to the simulator and half were prohibited access to the simulator while using the checklist . Residents rated their cognitive load in each step : prechecklist diagnosis , checklist use and postchecklist diagnosis . Result Verifying with a checklist result ed in improved diagnostic accuracy ; 88 residents ( 46 % ) made the correct diagnosis before using the checklist compared with 97 ( 51 % ) afterwards , p=0.04 . The benefit of checklist use was restricted to residents allowed to re-examine the simulator ( 10 changed to correct diagnosis and one to an incorrect diagnosis ) whereas no net benefit was seen among residents unable to re-examine the simulator ( two changed to a correct diagnosis and two to an incorrect diagnosis , p=0.03 ) . Those able to re-examine the simulator were slightly more confident after checklist use , whereas those unable to re-examine were slightly less confident after checklist use ( p=0.01 ) . The opportunity to re-examine the simulator had no effect on the accuracy of key findings reported . Of the three steps , checklist use was associated with the lowest cognitive load ( F1,189=68 p<0.001 ) . Conclusions Verifying diagnostic decisions with a checklist improved diagnostic accuracy . This benefit was only seen when more information could be collected . Checklist use was not associated with increased cognitive load Critical appraisal of research studies is the third step in evidence -based practice ( EBP ) , following step one , “ Asking clinical questions in PICO ( i.e. , population , intervention or interest area ; comparison intervention or group , and outcome of interest ) format , ” and step two , “ Search ing for evidence to answer the questions . ” Once research is found to answer a burning PICO clinical question ( e.g. , In teens , is cognitive-behavioral therapy or relaxation techniques more effective in reducing anxiety symptoms ? ) , the clinician must be able to rapidly appraise studies in order to determine their validity and applicability to clinical practice . For years , research courses in many educational curriculums have taught critiquing studies as a very detailed , time consuming process . Unfortunately , this method of teaching the appraisal process has often contributed to lasting negative attitudes about research and misperceptions by clinicians about the length of time that it takes to read and critically appraise a single research report . Many practicing clinicians also believe that critical appraisal is much too difficult or that experts in EBP and research ers are the only individuals who can be competent in the process . Therefore , this paper will present a user-friendly , efficient approach to critically appraising a published r and omized clinical trial ( RCT ) . Implementing this method of critical appraisal should contribute to enhanced confidence in clinicians ’ abilities to swiftly determine whether the findings from a RCT are valid and should be translated to their clinical practice setting Diagnostic tests are used to confirm , exclude , classify , or monitor disease to guide treatment . Their clinical value depends on whether the information they provide leads to improved patient outcomes ; this can be assessed by r and omized trials that compare patient outcomes from the new diagnostic test versus the old test strategy . However , r and omized trials of test- and -treatment strategies are not routinely performed . They are not required for marketing approval , and they are not always feasible because they require large sample sizes . As a result , new diagnostic tests frequently enter clinical practice without evidence of improved patient outcomes . Studies of diagnostic test accuracy can show how well diagnostic strategies that include a new test identify the presence or absence of disease compared with an old test strategy by comparing each with the results of a reference st and ard test . However , if clinicians use only information about test accuracy to decide whether to adopt a new diagnostic test , they sometimes may harm patients ( for example , if subsequent treatments are unsafe or ineffective ) . It is therefore worthwhile to investigate how best to decide if clinicians can rely on evidence about test accuracy or if they need to wait for patient outcome results from r and omized trials . Fryback and Thornbury ( 1 ) described a hierarchy of 6 levels of evidence for the assessment of a diagnostic test : 1 ) the technical quality of test information ; 2 ) diagnostic accuracy ; 3 ) change in the referring physician 's diagnostic thinking ; 4 ) change in the patient management plan ; 5 ) change in patient outcomes ; and 6 ) societal costs and benefits . This framework does not provide guidelines about if and when lower levels of evidence are adequate to assess a test and always requires r and omized trials for conclusions about improved patient outcomes . Some research ers have suggested that accuracy studies alone may sometimes suffice ( 2 - 6 ) . We provide a practical framework to help clinicians decide whether a new diagnostic test can be adopted on the basis of evidence of test accuracy alone or if they need to wait for results from r and omized trials . A Framework for Deciding if Evidence of Test Accuracy Will Suffice Studies of diagnostic test accuracy can suffice if clinicians already have evidence from r and omized trials showing that treatment of the cases detected by the diagnostic test improved patient outcomes ( Figure 1 ) . This approach may seem straightforward ; however , it requires a clear underst and ing of the proposed use and benefits of the new test , as well as careful consideration of whether the cases detected are representative of the patients included in treatment trials . Figure 1 . Trial evidence versus linked evidence of test accuracy and treatment efficacy . The benefits of a new diagnostic test will vary according to how it is used . Investigators of a new diagnostic test need to explicitly state who will be tested , where the new test will fit in the existing diagnostic pathway , and what tests it will supplement or replace . This information will allow them to identify the expected benefits of adopting the new test and , therefore , the most relevant questions to ask to assess its value . Test attributes generally fall into 3 categories : 1 ) The test is safer or is less costly ; 2 ) the test is more specific ( excludes more cases of nondisease ) and thus avoids unnecessary treatment ; and 3 ) the test is more sensitive ( detects more cases of disease ) and thus promotes more appropriate treatment . We propose a simple sequence of questions to guide decisions about whether evidence of test accuracy will suffice for each of these 3 categories ( Figure 2 ) . The first step in assessing a new diagnostic test is to classify it according to whether it is more sensitive than the old test . We describe the key concepts of this framework using simple examples to describe situations where the new test offers better safety or specificity with similar sensitivity , followed by consideration of situations where the test is more sensitive . We also consider other , more complex scenarios . In each of these examples , we have some existing evidence of treatment efficacy for cases detected by an old test , and therefore , the rationale for testing has already been established . Figure 2 . Assessing new tests using evidence of test accuracy , given that treatment is effective for cases detected by the old test . When a New Test Has Similar Sensitivity to an Old Test If a new diagnostic and old diagnostic test have similar sensitivity , it is generally reasonable to assume that they will detect the same true cases of disease . However , a new test may offer other positive attributes , such as better safety or more specificity than an old test . If studies of test accuracy show that the new test offers other positive attributes without a loss of sensitivity , it is logical to assume that cases detected by either test will show the same response to treatment . Therefore , new trials assessing treatment efficacy in the cases detected by the new test are not needed . When a new test and an old test show similar sensitivity and specificity , the value of the new test corresponds to the benefits of avoiding the adverse events or costs associated with the old test . For example , Doppler ultrasonography has been adopted as a less invasive replacement for venography for diagnosis of deep venous thrombosis ( 7 ) . Given that trials have shown that treatment of this condition is effective ( 8) , studies of test accuracy showing that Doppler ultrasonography and venography have similar sensitivity and specificity suffice to determine the value of the new test ( Table , example 1 ) . Table . New Diagnostic Test Assessment Framework and Examples If a new test is more specific than an old test , it avoids the harms of unnecessary further investigation or treatment . In this scenario , evidence showing that the new test has similar sensitivity but better specificity than the old test will suffice to determine the new test 's value . For example , new immunochemical fecal occult blood testing kits have been proposed to offer increased specificity , without a loss of sensitivity , for detecting human blood , reducing the high false-positive rate of the older guaiac-based test kits ( 9 ) . Given that trials have already shown the benefit of detecting colorectal cancer with guaiac test kits , studies of test accuracy will suffice to determine whether the immunochemical tests have increased specificity without any substantial loss in sensitivity ( Table , example 2 ) . Our assessment is more complex when we consider a new test that involves a tradeoff between positive and negative attributes . We deal with this situation later . When the New Test Is More Sensitive than the Old Test If a new test is more sensitive than an old test but has similar specificity , its value is directly related to the treatment response in the extra cases detected . If treatment response has already been assessed by treatment trials enrolling patients detected by the new test , decisions to use the test will be based on whether these trials showed that treatment improves patient outcomes . In this instance , evidence of test accuracy linked with evidence of treatment efficacy replaces the need for new r and omized trials ( Figure 1 ) . There will also be a good match between tested and treated population s if the results for patients identified by a new test are analyzed in a treatment trial as potential predictors of treatment response . For example , trials of adjuvant tamoxifen among women with early breast cancer have shown that the estrogen receptor status of the tumor determines its response to treatment ( 10 ) . These trials demonstrate the clinical value of testing for estrogen receptor status , as well as the effectiveness of  tamoxifen therapy . However , more commonly , treatment trials have only enrolled cases detected by an old test . In these situations , clinicians need to consider whether the results apply to cases detected by the new test . Assessing Whether the Extra Cases Detected by a New , More Sensitive  Test Respond to Treatment Clinicians first need to ask whether the extra cases detected by a new diagnostic test represent the same spectrum or subtypes of disease as those included in treatment trials . If they do , then r and omized trials may not be required ( Figure 2 ) . If they do not , or if clinicians can not be certain that they do , then clinicians also need to ask whether treatment response is known to be similar across the range of disease spectrum or subtype . These considerations are important regardless of the magnitude of the difference in sensitivity between tests . At one extreme , a good match between tested and treated population s is possible if the reference st and ard used to determine test sensitivity and specificity is also the starting point for trials conducted in similar population s. For example , computed tomography colonography is more sensitive for the detection of large colorectal polyps when scanning is performed with the patient in prone and supine positions versus supine positioning alone , without reduced specificity ( 11 ) . Treatment trials showing improved survival following the early detection and treatment of colorectal polyps have been based on cases detected by colonoscopy , the reference st and ard for the computed tomography colonography accuracy studies . All of these tests are used to identify the same disease characteristic ( adenomatous colorectal polyps ) and spectrum of disease ( classified by polyp size ) , so it is reasonable to conclude that computed tomography colonography with dual positioning will improve patient outcomes compared with supine positioning alone ( Table , example 3 ) . At the other extreme , a good match between tested and treated population s will not be possible if a new test measures a different biological characteristic to define disease and leads to a different selection of cases for treatment . For example , a new PURPOSE To determine how often practicing physicians use the customarily recommended quantitative methods that include sensitivity , specificity , and likelihood ratio indexes ; receiver operator characteristic ( ROC ) curves ; and Bayesian diagnostic calculations . PARTICIPANTS AND METHODS A r and om sample of 300 practicing physicians ( stratified by specialty to include family physicians , general internists , general surgeons , pediatricians , obstetrician/gynecologists , and internal medicine subspecialists ) were briefly interviewed in a telephone survey . They were asked about the frequency with which they used the formal methods , the reasons for non-use , and if they employed alternative strategies when appraising tests ' diagnostic accuracy . RESULTS Of the 300 surveyed physicians , 8 ( 3 % ) used the recommended formal Bayesian calculations , 3 used  ROC curves  , and 2 used  likelihood ratios .  The main reasons cited for non-use included impracticality of the Bayesian method ( 74 % ) , and nonfamiliarity with ROC curves and likelihood ratios ( 97 % ) . Of the 174 physicians who said they used sensitivity and specificity indexes , 165 ( 95 % ) did not do so in the recommended formal manner . Instead , the physicians directly estimated tests ' diagnostic accuracy by determining how often the test results were correct in groups of patients later found to have , or to be free of , the selected disease . CONCLUSIONS The results indicate that most practicing physicians do not use the formal recommended quantitative methods to appraise tests ' diagnostic accuracy , and instead report using an alternative direct approach . Although additional training might make physicians use the formal methods more often , the physicians ' direct method merits further evaluation as a potentially pragmatic tool for the determination of tests ' diagnostic accuracy in clinical practice Objective Early diagnosis of spondyloarthritis ( SpA ) is sometimes difficult owing to the lack of reliable diagnostic criteria . The objective of this study was to determine the diagnostic accuracy of detecting enthesitis by power Doppler ultrasonography ( PDUS ) in patients with suspected SpA. Methods A prospect i ve single-centre cohort study was performed in patients with symptoms suggestive of SpA ( inflammatory back pain , arthritis , enthesitis or dactylitis , HLAB27 + uveitis ) who underwent clinical examination , pelvic x-ray , MRI of lumbar spine/sacroiliac joints , HLA-B typing and other tests judged useful for diagnosis .  Blinded PDUS examination of seven sites of enthesitis was performed at baseline . The gold st and ard was the diagnosis made by the referring rheumatologist according to the development of symptoms and findings , blinded to PDUS results , during routine follow-up for up to 2 years . Results Between November 2002 and October 2004 , 118 patients were included in the study . After 2 years a definite diagnosis was retained for 99 patients ( 51 SpA and 48 non-SpA ) .  PDUS detection of at least one vascularised enthesis provided good predictive value for diagnosing SpA ( sensitivity 76.5 % ; specificity 81.3 % ; positive likelihood ratio 4.1 ; OR 14.1 ; p<0.0001 ) . Vascularised enthesitis detected by PDUS and Amor 's criteria were the only independent contributors to a diagnosis of SpA in multivariate logistic regression ( c-index=0.87 ) . Alternatively , CART analysis result ed in a highly sensitive and specific diagnostic tree by combining PDUS with Amor 's criteria . Conclusions PDUS appears to be a valuable first-line diagnostic tool to confirm a diagnosis of OBJECTIVE To optimize referral to specialized gynaecologists for surgical treatment of ovarian cancer by improving preoperative discrimination between benign and malignant pelvic tumours . STUDY DESIGN In a prospect i ve multicentre study 143 patients with a pelvic mass were included . At several occasions during the diagnostic work-up the gynaecologist estimated the chance of malignancy ( educated guess/expert opinion ) . MRI in the local setting was suggested for uncertain cases . All MRI images were review ed by an expert radiologist . The data sheet design ed for the study further allowed for determining the risk of malignancy index ( RMI ) . RESULTS The diagnostic accuracy of the gynaecologist 's final estimation of the chance of malignancy and the calculated RMI were comparable ( area under the ROC curve of 0.87 and 0.86 ) . MRI did not improve the accuracy of the diagnostic work-up for the study population as a whole . Subgroup analysis did however show improved diagnostic accuracy in cases with an estimated chance of malignancy between 20 and 80 % when the MRI was read by an expert radiologist . CONCLUSION Patient selection for surgery of a pelvic mass should be based on the chance of malignancy as assigned by the referring gynaecologists . In case of uncertainty MRI improves diagnostic accuracy , when judged by an expert Study Design . A blinded , prospect i ve diagnostic test study was conducted . Objectives . To assess the reliability and accuracy of individual clinical examination items  and  self-report instruments  for the diagnosis of cervical radiculopathy , and to identify and assess the accuracy of an optimum test-item cluster for the diagnosis of cervical radiculopathy . Summary of Background Data . Although cervical radiculopathy remains largely a clinical diagnosis , the reliability and diagnostic accuracy of clinical examination items , individually or in combination , for cervical radiculopathy is largely unknown . Methods . Patients with suspected cervical radiculopathy or carpal tunnel syndrome received st and ardized electrophysiologic examination of the symptomatic upper quarter followed by a st and ardized clinical examination by physical therapist examiners blinded to diagnosis . Diagnostic properties were assessed using a neural impairment reference criterion st and ard . Results . The study involved 82 patients . More than two thirds of 34 clinical examination items had reliability coefficients rated at least fair or better , and 13 items had likelihood ratio point estimates above 2 or below 0.50 . A single diagnostic test item cluster of four variables was identified and produced a positive likelihood ratio point estimate of 30.3 . The 95 % confidence intervals for all likelihood ratio point estimates in this study were wide . Conclusions . Many items of the clinical examination were found to be reliable and to have acceptable diagnostic properties , but the test item cluster identified was more useful for indicating cervical radiculopathy than any single test item . Upper limb tension Test A was the most useful test for ruling out cervical radiculopathy . Further investigation is required both to vali date the test item cluster and to improve point estimate precision BACKGROUND Although many patients are evaluated initially by their general practitioner , clinicians ' accuracy at diagnosing organic gastrointestinal disease has not been studied in a primary care setting . Different spectra of severity of disease in general practice and hospital population s may lead to different values for diagnostic tests in these two population s. AIM This study set out to determine the diagnostic value of history and physical and laboratory items for organic and neoplastic disease in general practice patients with nonacute abdominal complaints . METHOD The one-year prospect i ve , observational study was carried out in 1989 in 80 general practice s in Limburg , the Netherl and s. The study subjects were 933 patients ( aged 18 - 75 years ) presenting to their general practitioner with new non-acute abdominal complaints of minimum duration two weeks , and with whom the doctor had a diagnostic problem . Patients were physically examined by their general practitioner and asked to complete pre-structured question naires . Basic laboratory tests were carried out . Patients were followed up for at least one year by research ers and then a diagnosis was determined by an independent panel of three general practitioners using patient records , blinded for the results of the question naires . Sensitivity , specificity and odds ratios were calculated for clinical items . Stepwise forward logistic regression analysis was undertaken to identify independent predictors of organic gastrointestinal disease . RESULTS Of the 933 patients 14 % had organic gastrointestinal disease . No clinical item had both high sensitivity and specificity . Logistic regression analysis showed only eight independent predictors of organic disease : male sex , greater age , epigastric pain , no specific character to pain , pain affecting sleep , history of blood in stool , no pain relief after defecation and abnormal white blood cell count . When the model was programmed to predict neoplasms five items were found : male sex , greater age , no specific character to pain , weight loss and erythrocyte sedimentation rate greater than 20 mm hour-1 . CONCLUSION In a general practice population with non-acute abdominal complaints some clinical findings can be used as predictors for organic and neoplastic gastrointestinal disease OBJECTIVES To review UK guidelines regarding the use of financial incentives for healthcare professionals to become involved in clinical trials , and to survey perceptions and current practice . DATA SOURCES Electronic data bases were search ed from inception to June 2006 . Interviews were held with NHS healthcare professionals , research managers from the pharmaceutical industry and members of the public . REVIEW METHODS From the search es , 634 identified studies were assessed for inclusion in the systematic review , but only three met the criteria for data extraction . Fifty-eight individuals were interviewed : 38 chief investigators , six non- research active clinicians , eight public and six pharmaceutical managers . Investigators were selected from those funded by the HTA Programme , the other by ' snowballing ' and personal contact . RESULTS The evidence from the literature was limited and inconclusive . In UK guidelines , the issues around payments to clinicians or patients were implied rather than stated , usually linked to discussion of conflict of interest and disclosure of any such conflicts . Developments in NHS research governance had led to increased transparency in all payments for research participation and for payments to be made to NHS Trusts rather than individual clinicians . While reimbursement of costs incurred by research was strongly supported by the interviewees , payments to incentivise recruitment were not . A code of practice was suggested for payments in publicly funded trials , which was closely linked to the principles of Good Clinical Practice in research . Factors such as interest in the topic , scope for patient benefit and good communication were considered more important than payment . Interviews with the general public indicated low levels of awareness of the existence of payments to clinicians linked to patient recruitment in trials , and unanimous support for full disclosure . Interviews with managers in the pharmaceutical industry showed greater familiarity with payments for research involvement . GPs were seen as the only group for whom scope existed for individual payments . Concerns were expressed by the pharmaceutical company interviewees at the rising cost of research and unnecessary bureaucracy . CONCLUSIONS The ethical stances outlined in Good Clinical Practice in research were widely endorsed by the three groups interviewed . These allow reasonable payments to clinicians , subject to disclosure of any possible conflicts of interest . The potential for incentivising clinicians to recruit was limited as any payments should be based on the cost of inputs and should not be made to individuals but to their host organisation . NHS professionals were concerned that payments could damage the quality of research and also considered full disclosure to patients as challenging . Patients and members of the public favoured full disclosure and payment of expenses to patients involved in research . Pharmaceutical company interviewees viewed payment to the NHS for all research activities as normal and highly regulated . They complained that the prices charged were high and so variable that they required benchmarking . Considerable scope exists for compiling data on the factors that help and hinder the progress of clinical trials and also for experimenting with different incentives to encourage involvement in clinical research . Further research should focus on improved reporting of those organisational aspects of trials that are known to affect recruitment ; retrospective analysis of the factors associated with different levels of recruitment to RCTs ; prospect i ve comparative research on trial recruitment ; qualitative research on participants ' experiences of being involved in different kinds of trials , and proposals to include within trials experiments with payments methods PURPOSE To investigate the diagnostic accuracy and association to disability of selected functional findings or physical examination tests for patellofemoral pain syndrome ( PFPS ) in patients with anterior knee pain . METHODS A sample of 76 consecutive patients with anterior knee pain was further subdivided into PFPS and other diagnoses . Routine physical examination tests were examined in a prospect i ve , consecutive-subjects design for a cohort of patients with anterior knee pain . Diagnostic accuracy findings , including sensitivity , specificity , positive ( PPV ) and negative ( NPV ) predictive value , and positive ( LR+ ) and negative ( LR- ) likelihood ratios , were calculated for each test . PPV and NPV reflect the percentage of time of positive or a negative test ( respectively ) accurately captures the diagnosis of the condition . LR+ and LR- reflect alterations in post-test probability when the test is positive or negative ( respectively ) . Lastly , associations to disability ( International Knee Documentation Committee ( IKDC ) subjective form ) were calculated for each clinical finding . RESULTS Diagnostic accuracy analyses of individual functional assessment and situational phenomena suggest that the strongest diagnostic test is pain encountered during resisted muscle contraction of the knee ( PPV=82 % ; LR+=2.2 ; 95 % CI : 0.99 - 5.2 ) . Clusters of test findings were substantially more diagnostic , with any two of three positive findings of muscle contraction , pain during squatting , and pain during palpation yielding the following values : PPV=89 % ; LR+=4.0 ( 95 % CI : 1.8 - 10.3 ) . No individual or clustered test findings were significantly associated with the IKDC score . CONCLUSION Combinations of functional assessment tests and situational phenomena are diagnostic for PFPS and may serve to rule in and rule out the presence of PFPS . Single findings are not related to disability scores ( IKDC ) Despite long-st and ing critiques of the conduct of underpowered clinical trials , the practice not only remains widespread , but also has garnered increasing support . Patients and healthy volunteers continue to participate in research that may be of limited clinical value , and authors recently have offered 2 related arguments to support the validity and value of underpowered clinical trials : that meta- analysis may " save " small studies by providing a means to combine the results with those of other similar studies to enable estimates of an intervention 's efficacy , and that although small studies may not provide a good basis for testing hypotheses , they may provide valuable estimates of treatment effects using confidence intervals . In this article , we examine these arguments in light of the distinctive moral issues associated with the conduct of underpowered trials , the disclosures that are owed to potential participants in underpowered trials so they may make autonomous enrollment decisions , and the circumstances in which the prospect s for future meta-analyses may justify individually underpowered trials . We conclude that underpowered trials are ethical in only 2 situations : small trials of interventions for rare diseases in which investigators document explicit plans for including their results with those of similar trials in a prospect i ve meta- analysis , and early-phase trials in the development of drugs or devices , provided they are adequately powered for defined purpose s other than r and omized treatment comparisons . In both cases , investigators must inform prospect i ve subjects that their participation may only indirectly contribute to future health care benefits Research into the diagnostic accuracy of clinical tests is often hampered by single or double partial verification mechanisms , that is , not all patients have their disease status verified by a reference test , neither do all patients receive all tests under evaluation ( index tests ) . We show methods that reduce verification bias introduced when omitting data from partially tested patients . Adjustment techniques are well established when there are no missing index tests and when the reference test is ' missing at r and om ' . However , in practice , index tests tend to be omitted , and the choice of applying a reference test may depend on unobserved variables related to disease status , that is , verification may be missing not at r and om ( MNAR ) . We study  double partial verification  in a clinical example from reproductive medicine in which we analyse the diagnostic values of the  chlamydia antibody  test and the  hysterosalpingography  in relation to a diagnostic laparoscopy . First , we plot all possible combinations of sensitivity and specificity of both index tests in two test ignorance regions . Then , we construct models in which we impose different assumptions for the verification process . We allow for missing index tests , study the influence of patient characteristics and study the accuracy estimates if an MNAR mechanism would operate . It is shown that data on tests used in the diagnostic process of the same population are preferably studied jointly and that the influence of an MNAR verification process was limited in a clinical study where more than half of the patients did not have the reference test Study Design This prospect i ve study evaluated the diagnostic utility of historically accepted sacroiliac joint tests . A multidisciplinary expert panel recommended 12 of the “ best ” sacroiliac joint tests to be evaluated against a criterion st and ard of unequivocal pain relief after an intra‐articular injection of local anesthetic into the sacroiliac joint . Objectives To identify a single sacroiliac joint test or ensemble of tests that are sufficiently useful in diagnosing sacroiliac joint disorders to be clinical ly valuable . Summary of Background Data No previous research has been done to evaluate any physical test of sacroiliac joint pain against an accepted criterion st and ard . Methods Historical data was obtained , and the 12 tests were performed by two examiners on 85 patients who subsequently underwent sacroiliac joint blocks .  Ninety percent or more relief was considered a positive response , and less then 90 % relief was considered a negative response . Results There were 45 positive and 40 negative responses . No historical feature , none of the 12 sacroiliac joint tests , and no ensemble of these 12 tests demonstrated worthwhile diagnostic value . Conclusion Sacroiliac joint pain is resistant to identification by the historical and physical examination data from tests evaluated in this study OBJECTIVE We developed AsthmaCritic , a non-inquisitive critiquing system integrated with the general practitioners ' electronic medical records . The system is based on the guidelines for asthma and chronic obstructive pulmonary disease ( COPD ) as issued by the Dutch College of General Practitioners . This paper assesses the effect of AsthmaCritic on monitoring and treatment of asthma and COPD by Dutch general practitioners in daily practice . METHODS A r and omized clinical trial in 32 practice s ( 40 Dutch general practitioners ) using electronic patient records . An intervention group was given the use of AsthmaCritic , a control group continued working in the usual manner . Both groups had the disposal of the asthma and COPD guidelines routinely distributed by the Dutch College of General Practitioners . We measured the average number of contacts , FEV 1 ( forced expiratory volume ) , and peak-flow measurements per asthma/ COPD patient per practice ; and , the average number of antihistamine , cromoglycate , deptropine , and oral bronchodilator prescriptions  per asthma/ COPD patient per practice . RESULTS The number of contacts increased in the age group of 12 - 39 years . The number of FEV1 , peak-flow measurements , and the ratio of coded measurements increased , whereas the number of cromoglycate prescriptions decreased in the age group of 12 - 39 years . CONCLUSIONS Our study shows that the guideline -based critiquing system AsthmaCritic changed the manner in which the physicians monitored their patients and , to a lesser extent , their treatment behavior . In addition , the physicians changed their data -recording habits OBJECTIVE To compare the accuracy of combinations of clinical examination findings for predicting a positive response to injection of local anaesthetic into the subacromial bursa . DESIGN Prospect i ve , cohort , diagnostic validity design . SUBJECTS Consecutive patients with shoulder pain recruited from primary care physiotherapy and general medical practice s. METHODS All subjects underwent a st and ardised clinical examination ( index test ) followed by a diagnostic injection of xylocaineTM into the subacromial bursa ( reference st and ard test ) performed under ultrasound guidance . Clinical examination variables associated with a positive anaesthetic response ( ≥ 80 % post-injection reduction in pain intensity ) were identified ( p < 0.20 ) and diagnostic accuracy was calculated . RESULTS Of the 196 subjects who received a subacromial bursa injection , 66 subjects ( 34 % ) reported a positive anaesthetic response . Strain injury ( adjusted odds ratio ( AOR ) 2.3 ) , anterior shoulder pain ( AOR 2.3 ) and absence of pain with external rotation at 90º abduction ( AOR 3.9 ) were the strongest clinical predictors of positive anaesthetic response . Clinical prediction model variables demonstrated 100 % specificity ( 3 positive tests ) but low sensitivity ( maximum 40 % ) for a positive anaesthetic response . Combinations of 9 other clinical variables also demonstrated 100 % specificity ( 7 or more positive tests ) , and improved sensitivity ( 95 to 100 % ) for a PAR compared with clinical prediction model variables when less than two findings were present . CONCLUSION Combinations of these clinical tests may assist the clinician to differentiate subacromial pain from other shoulder conditions and guide selection of targeted pain management interventions . Additional diagnostic tests may be required when clinical criteria are not satisfied Diagnosis is a critical component of health care , and clinicians , policymakers , and patients routinely face a range of questions regarding diagnostic tests . They want to know whether testing improves outcome ; what test to use , purchase , or recommend in practice guidelines ; and how to interpret test results . Well- design ed  diagnostic test accuracy studies can help in making these decisions , provided that they transparently and fully report their participants , tests , methods , and results as facilitated , for example , by the STARD ( St and ards for Reporting of Diagnostic Accuracy ) statement ( 1 ) . That 25-item checklist was published in many journals and is now adopted by more than 200 scientific journals worldwide . As in other areas of science , systematic review s and meta- analysis of accuracy studies can be used to obtain more precise estimates when small studies addressing the same test and patients in the same setting are available . Review s can also be useful to establish whether and how scientific findings vary by particular subgroups , and may provide summary estimates with a stronger generalizability than estimates from a single study . Systematic review s may help identify the risk for bias that may be present in the original studies and can be used to address questions that were not directly considered in the primary studies , such as comparisons between tests . The Cochrane Collaboration is the largest international organization preparing , maintaining , and promoting systematic review s to help people make well-informed decisions about health care ( 2 ) . The Collaboration decided in 2003 to make preparations for including systematic review s of diagnostic test accuracy in their Cochrane Data base of Systematic Review s. To enable this , a working group ( Appendix ) . was formed to develop methodology , software , and a h and book The first diagnostic test accuracy review was published in the Cochrane Data base in October 2008 . In this paper , we review recent method ological developments concerning problem formulation , location of literature , quality assessment , and meta- analysis of diagnostic accuracy studies by using our experience from the work on the Cochrane H and book . The information presented here is based on the recent literature and up date s previously published guidelines by Irwig and colleagues ( 3 ) . Definition of the Objectives of the Review Diagnostic test accuracy refers to the ability of a test to distinguish between patients with disease ( or more generally , a specified target condition ) and those without . In a study of test accuracy , the results of the test under evaluation , the index test , are compared with those of the reference st and ard determined in the same patients . The reference st and ard is an agreed-on and accurate method for identifying patients who have the target condition . Test results are typically categorized as positive or negative for the target condition . By using such binary test outcomes , the accuracy is most often expressed as the test 's sensitivity ( the proportion of patients with positive results on the reference st and ard that are also positive on the index test ) and specificity ( the proportion of patients with negative results on the reference st and ard that are also negative on the index test ) . Other measures have been proposed and are in use ( 46 ) . It has long been recognized that test accuracy is not a fixed property of a test . It can vary between patient subgroups , with their spectrum of disease , with the clinical setting , or with the test interpreters and may depend on the results of previous testing . For this reason , inclusion of these elements in the study question is essential . In order to make a policy decision to promote use of a new index test , evidence is required that using the new test increases test accuracy over other testing options , including current practice , or that the new test has equivalent accuracy but offers other advantages ( 79 ) . As with the evaluation of interventions , systematic review s need to include comparative analyses between alternative testing strategies and should not focus solely on evaluating the performance of a test in isolation . In relation to the existing situation , 3 possible roles for a new test can be defined : replacement , triage , and add-on ( 7 ) . If a new test is to replace an existing test , then comparing the accuracy of both tests on the same population and with the same reference st and ard provides the most direct evidence . In triage , the new test is used before the existing test or testing pathway , and only patients with a particular result on the triage test continue the testing pathway . When a test is needed to rule out disease in patients who then need no further testing , a test that gives a minimal proportion of falsenegative results and thus a relatively high sensitivity should be used . Triage tests may be less accurate than existing ones , but they have other advantages , such as simplicity or low cost . A third possible role of a new test is add-on . The new test is then positioned after the existing testing pathway to identify false-positive or false-negative results after the existing pathway . The review should provide data to assess the incremental change in accuracy made by adding the new test . An example of a replacement question can be found in a systematic review of the diagnostic accuracy of urinary markers for primary bladder cancer ( 10 ) . Clinicians may use cytology to triage patients before they undergo invasive cystoscopy  , the reference st and ard for bladder cancer . Because cytology combines high specificity with low sensitivity ( 11 ) , the goal of the review was to identify a tumor marker with sufficient accuracy to either replace cytology or be used in addition to cytology . For a marker to replace cytology , it has to achieve equally high specificity with improved sensitivity . New markers that are sensitive but not specific may have roles as adjuncts to conventional testing . The review included studies in which the test under evaluation ( several different tumor markers and cytology ) was evaluated against cystoscopy or histopathology . Included studies compared 1 or more of the markers , cytology only , or a combination of markers and cytology . Although information on accuracy can help clinicians make decisions about tests , good diagnostic accuracy is a desirable but not sufficient condition for the effectiveness of a test ( 8) . To demonstrate that using a new test does more good than harm to patients tested , r and omized trials of test- and -treatment strategies and review s of such trials may be necessary . However , with the possible exception of screening , in most cases , such r and omized trials are not available and systematic review s of test accuracy may provide the most useful evidence available to guide clinical and health policy decision making and use as input for decision and cost-effectiveness analysis ( 12 ) . Identification and Selection of Studies Identifying test accuracy studies is more difficult than search ing for r and omized trials ( 13 ) . There is not a clear , unequivocal keyword or indexing term for an accuracy study in literature data bases comparable with the term r and omized , controlled trial . The Medical Subject Heading sensitivity and specificity may look suitable but is inconsistently applied in most electronic bibliographic data bases . Furthermore , data on diagnostic test accuracy may be hidden in studies that did not have test accuracy estimation as their primary objective . This complicates the efficient identification of diagnostic test accuracy studies in electronic data bases , such as MEDLINE . Until indexing systems properly code studies of test accuracy , search ing for them will remain challenging and may require additional manual search es , such as screening reference lists . In the development of a comprehensive search strategy , review authors can use search strings that refer to the test(s ) under evaluation , the target condition , and the patient description or a subset of these . For tests with a clear name that are used for a single purpose , search ing for publications in which those tests are mentioned may suffice . For other review s , adding the patient description may be necessary , although this is also often poorly indexed . A search strategy in MEDLINE should contain both Medical Subject Headings and free text words . A search strategy for articles about tests for bladder cancer , for example , should include as many synonyms for bladder cancer as possible in the search strategy , including neoplasm , carcinoma , transitional cell , and hematuria . Several method ological electronic search filters for diagnostic test accuracy studies have been developed , each attempting to restrict the search to articles that are most likely to be test accuracy studies ( 1316 ) . These filters rely on indexing terms for research methodology and text words used in reporting results , but they often miss relevant studies and are unlikely to decrease the number of articles one needs to screen . Therefore , they are not recommended for systematic review s ( 17 , 18 ) . The incremental value of search ing in language s other than English and in the gray literature has not yet been fully investigated . In systematic review s of intervention studies , publication bias is an important and well-studied form of bias in which the decision to report and publish studies is linked to their findings . For clinical trials , the magnitude and determinants of publication bias have been identified by tracing the publication history of cohorts of trials review ed by ethics committees and research boards ( 19 ) . A consistent observation has been that studies with significant results are more likely to be published than studies with nonsignificant findings ( 19 ) . Investigating publication bias for diagnostic tests is problematic , because many studies are done without ethical review or study registration ; therefore , identification of cohorts of studies from registration to final publication status Accurate detection and classification of aspiration is a critical component of videofluoroscopic swallowing evaluation , the most commonly utilized instrumental method for dysphagia diagnosis and treatment . Currently published literature indicates that interjudge reliability for the identification of aspiration ranges from poor to fairly good depending on the amount of training provided to clinicians . The majority of extant studies compared judgments among clinicians . No studies included judgments made during the use of a postural compensatory strategy . The purpose of this study was to examine the accuracy of judgments made by speech- language pathologists ( SLPs ) practicing in hospitals compared with unblinded expert judges when identifying aspiration and using the 8-point Penetration/Aspiration Scale .  Clinicians received extensive training for the detection of aspiration and minimal training on use of the Penetration/Aspiration Scale . Videofluoroscopic data were collected from 669 patients as part of a large , r and omized clinical trial and include judgments of 10,200 swallows made by 76 clinicians from 44 hospitals in 11 states . Judgments were made on swallows during use of dysphagia compensatory strategies : chin-down posture with thin liquids and head-neutral posture with thickened liquids ( nectar-thick and honey-thick consistencies ) . The subject population included patients with Parkinson ’s disease and /or dementia .  Kappa statistics indicate high accuracy for all interventions by SLPs for identification of aspiration ( all κ > 0.86 ) and variable accuracy ( range = 69–76 % ) using the Penetration/Aspiration Scale when compared to expert judges . It is concluded that while the accuracy of identifying the presence of aspiration by SLPs is excellent , more extensive training and /or image enhancement is recommended for precise use of the Penetration/Aspiration Scale
No tests for impingement or acromioclavicular ( AC ) joint pathology demonstrated significant diagnostic accuracy .
Based on pooled data , the diagnostic accuracy of the Neer test for impingement , the Hawkins-Kennedy test for impingement and the Speed test for labral pathology is limited .
Currently , almost without exception , there is a lack of clarity with regard to whether common OSTs used in clinical examination are useful in differentially diagnosing pathologies of the shoulder
OBJECTIVE To compile and critique research on the diagnostic accuracy of individual  orthopaedic physical examination tests in a manner that would allow clinicians to judge whether these tests are valuable to their practice .