Estimating the Minimal Important Difference for the Western Ontario Rotator Cuff Index (WORC) in adults with shoulder pain associated with partial-thickness rotator cuff tears. Responsiveness and Minimal Clinically Important Change: A Comparison Between 2 Shoulder Outcome Measures. The Responsiveness and Minimal Important Change of the Western Ontario Shoulder Instability Index and Oxford Shoulder Instability Score Subacromial decompression versus diagnostic arthroscopy for shoulder impingement: randomised, placebo surgery controlled clinical trial Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial Exercises versus arthroscopic decompression in patients with subacromial impingement: a randomised, controlled study in 90 cases with a one year follow up. A combination of distribution- and anchor-based approaches determined minimally important differences (MIDs) for four endpoints in a breast cancer scale. Minimal important changes in the Constant-Murley score in patients with subacromial pain. The CSAW Study (Can Shoulder Arthroscopy Work?) – a placebo-controlled surgical intervention trial assessing the clinical and cost effectiveness of arthroscopic subacromial decompression for shoulder pain: study protocol for a randomised controlled trial Minimally important difference for the Expanded Prostate Cancer Index Composite Short Form. Predictive value of preoperative clinical examination for subacromial decompression in impingement syndrome A new interdisciplinary treatment strategy versus usual medical care for the treatment of subacromial impingement syndrome: a randomized controlled trial Are Psychologic Factors Associated With Shoulder Scores After Rotator Cuff Surgery? Finnish Subacromial Impingement Arthroscopy Controlled Trial (FIMPACT): a protocol for a randomised trial comparing arthroscopic subacromial decompression and diagnostic arthroscopy (placebo control), with an exercise therapy control, in the treatment of shoulder impingement syndrome
BACKGROUND Knowledge about Minimal Important Differences ( MIDs ) is essential for the interpretation of continuous outcomes , especially patient-reported outcome measures ( PROMS ) . OBJECTIVE The aim of this study was to estimate the MID for the Western Ontario Rotator Cuff Index ( WORC : score 0 ( best ) to 2100 ( worst disability ) ) in adults with shoulder pain associated with partial-thickness rotator cuff tears , ' symptomatic PTTs ' , undergoing conservative treatment with physiotherapy . DESIGN A prospect ively- design ed anchor-based MID analysis using data from a prospect i ve prognostic study with a three-month follow-up conducted within an outpatient care setting in Germany . METHODS The MID was estimated using data from 64 adults with atraumatic symptomatic PTTs who underwent three months of conservative treatment with physiotherapy .  The anchor was a seven-point Global Perceived Change ( GPC ) scale . RESULTS Based on a definition of the MID being the threshold of " being ( at least slightly ) improved " with a probability nearest to 0.90 ( i.e. 9 of 10 patients achieving the MID ) , the MID for the WORC was estimated as -300 for ' improved ' shoulder-related disability in 9 out of 10 patients ( 95 % CI 8 out of 10 patients to everyone ) undergoing three months of exercise-based physiotherapy for symptomatic PTTs . CONCLUSIONS This is the first published MID estimate for the WORC in adults with symptomatic PTTs of the rotator cuff undergoing typical treatment comprising conservative treatment with physiotherapy . The conceptual framework for interpretation facilitates its use in similar clinical context Study Design A prospect i ve cohort study nested in a r and omized controlled trial . Objectives To determine and compare responsiveness and minimal clinical ly important change of the  modified Constant score ( CS )  and the  Oxford Shoulder Score ( OSS ) .  Background The OSS and the CS are commonly used to assess shoulder outcomes . However , few studies have evaluated the measurement properties of the OSS and CS in terms of responsiveness and minimal clinical ly important change . Methods The study included 126 patients who reported having difficulty returning to usual activities 8 to 12 weeks after arthroscopic decompression surgery for subacromial impingement syndrome . The assessment at baseline and at 3 months included the  OSS , the CS  , and the  European Quality of Life-5 Dimensions-3 Level ( EQ-5D-3L ) index . Responsiveness was assessed as follows : by correlation analysis between the change scores of the OSS , CS , and EQ-5D-3L index , and the Patient Global Impression of Change ( PGIC ) scale ; by receiver-operating-characteristic ( ROC ) curve analysis using the PGIC scale as an external anchor ; and by effect-size statistics . Results At 3 months , a follow-up assessment of 112 patients ( 89 % ) was conducted . The change scores of the CS and the OSS were more strongly correlated with the external anchor ( PGIC scale ) than the change score of the EQ-5D-3L index . The areas under the ROC curves exceeded 0.80 for both shoulder scores , with no significant differences between them , and comparable effect-size estimates were observed for the CS and the OSS . Minimal clinical ly important change ROC values were 6 points for the OSS and 11 points for the CS , with upper 95 % cutoff limits of 12 and 22 points , respectively . Conclusion The CS and the OSS were both suitable for assessing improvement after decompression surgery • STUDY DESIGN : Prospect i ve cohort study . • BACKGROUND : Patient‐reported outcome measurements ( PROMs ) are widely used to evaluate functional limitations . Considering PROMs for shoulder instability , information is lacking with regard to what constitutes a relevant change from baseline scores . • OBJECTIVES : To evaluate the responsiveness of the Western Ontario Shoulder Instability Index ( WOSI ) and the  Oxford Shoulder Instability Score ( OSIS ) and estimate their minimal important change ( MIC ) . • METHODS : One hundred five consecutive patients with shoulder instability completed 5 PROMs at baseline and at 6‐month follow‐up . The PROMs included the  WOSI and OSIS , the Simple Shoulder Test , the Oxford Shoulder Score , and the Disabilities of the Arm , Shoulder and H and assessment .  Patients also rated their functional change on an anchor question at follow‐up . Responsiveness was evaluated by testing 9 hypotheses regarding predefined correlations between the changes in PROM scores , by calculating the area under the receiver operating characteristic curve and by calculating the st and ardized response mean and effect size statistics . The MIC was determined by identifying the optimal cutoff on the receiver operating characteristic curve . • RESULTS : Seven out of 9 hypotheses ( 78 % ) were confirmed ; as expected , a high correlation ( 0.77 ) was found between change scores of the WOSI and OSIS , whereas the correlations of the change scores of the WOSI and OSIS with those of general shoulder PROMs were slightly lower ( 0.61‐0.75 ) . The area under the curve was 0.83 ( 95 % confidence interval : 0.75 , 0.91 ) for the OSIS and 0.82 ( 95 % confidence interval : 0.74 , 0.90 ) for the WOSI . The MIC was about 6 points for the OSIS and about 14 points for the WOSI . • CONCLUSION : Both the WOSI and OSIS are able to measure change in shoulder function in patients with shoulder instability . The estimated MIC is 6 points for the OSIS ( on a scale from 0 to 48 ) and 14 points for the WOSI ( on a scale from 0 to 100 ) . •KEY WORDS : clinimetrics , functional outcome measures , outcome assessment , Abstract Objective To assess the efficacy of arthroscopic subacromial decompression ( ASD )  by comparing it with diagnostic arthroscopy , a placebo surgical intervention , and with a non-operative alternative , exercise therapy , in a more pragmatic setting . Design Multicentre , three group , r and omised , double blind , sham controlled trial . Setting Orthopaedic departments at three public hospitals in Finl and . Participants 210 patients with symptoms consistent with shoulder impingement syndrome , enrolled from 1 February 2005 with two year follow-up completed by 25 June 2015 . Interventions ASD , diagnostic arthroscopy ( placebo control ) , and exercise therapy . Main outcome measures Shoulder pain at rest and on arm activity ( visual analogue scale ( VAS ) from 0 to 100 , with 0 denoting no pain ) , at 24 months . The threshold for minimal clinical ly important difference was set at 15 . Results In the primary intention to treat analysis ( ASD versus diagnostic arthroscopy ) , no clinical ly relevant between group differences were seen in the two primary outcomes at 24 months ( mean change for ASD 36.0 at rest and 55.4 on activity ; for diagnostic arthroscopy 31.4 at rest and 47.5 on activity ) . The observed mean difference between groups ( ASD minus diagnostic arthroscopy ) in pain VAS were −4.6 ( 95 % confidence interval −11.3 to 2.1 ) points ( P=0.18 ) at rest and −9.0 ( −18.1 to 0.2 ) points ( P=0.054 ) on arm activity . No between group differences were seen between the ASD and diagnostic arthroscopy groups in the secondary outcomes or adverse events . In the secondary comparison ( ASD versus exercise therapy ) , statistically significant differences were found in favour of ASD in the two primary outcomes at 24 months in both VAS at rest ( −7.5 , −14.0 to −1.0 , points ; P=0.023 ) and VAS on arm activity ( −12.0 , −20.9 to −3.2 , points ; P=0.008 ) , but the mean differences between groups did not exceed the pre-specified minimal clinical ly important difference . Of note , this ASD versus exercise therapy comparison is not only confounded by lack of blinding but also likely to be biased in favour of ASD owing to the selective removal of patients with likely poor outcome from the ASD group , without comparable exclusions from the exercise therapy group . Conclusions In this controlled trial involving patients with a shoulder impingement syndrome , arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy at 24 months . Trial registration Clinical trials.gov NCT00428870 Summary Background Arthroscopic sub-acromial decompression ( decompressing the sub-acromial space by removing bone spurs and soft tissue arthroscopically ) is a common surgery for subacromial shoulder pain , but its effectiveness is uncertain . We did a study to assess its effectiveness and to investigate the mechanism for surgical decompression . Methods We did a multicentre , r and omised , pragmatic , parallel group , placebo-controlled , three-group trial at 32 hospitals in the UK with 51 surgeons . Participants were patients who had subacromial pain for at least 3 months with intact rotator cuff tendons , were eligible for arthroscopic surgery , and had previously completed a non-operative management programme that included exercise therapy and at least one steroid injection . Exclusion criteria included a full-thickness torn rotator cuff . We r and omly assigned participants ( 1:1:1 ) to arthroscopic subacromial decompression , investigational arthroscopy only , or no treatment ( attendance of one re assessment appointment with a specialist shoulder clinician 3 months after study entry , but no intervention ) . Arthroscopy only was a placebo as the essential surgical element ( bone and soft tissue removal ) was omitted . We did the r and omisation with a computer-generated minimisation system . In the surgical intervention groups , patients were not told which type of surgery they were receiving ( to ensure masking ) . Patients were followed up at 6 months and 1 year after r and omisation ; surgeons coordinated their waiting lists to schedule surgeries as close as possible to r and omisation . The primary outcome was the Oxford Shoulder Score ( 0 [ worst ] to 48 [ best ] ) at 6 months , analysed by intention to treat . The sample size calculation was based upon a target difference of 4·5 points ( SD 9·0 ) . This trial has been registered at Clinical Trials.gov , number NCT01623011 . Findings Between Sept 14 , 2012 , and June 16 , 2015 , we r and omly assigned 313 patients to treatment groups ( 106 to decompression surgery , 103 to arthroscopy only , and 104 to no treatment ) . 24 [ 23 % ] , 43 [ 42 % ] , and 12 [ 12 % ] of the decompression , arthroscopy only , and no treatment groups , respectively , did not receive their assigned treatment by 6 months . At 6 months , data for the Oxford Shoulder Score were available for 90 patients assigned to decompression , 94 to arthroscopy , and 90 to no treatment . Mean Oxford Shoulder Score did not differ between the two surgical groups at 6 months ( decompression mean 32·7 points [ SD 11·6 ] vs arthroscopy mean 34·2 points [ 9·2 ] ; mean difference −1·3 points ( 95 % CI −3·9 to 1·3 , p=0·3141 ) . Both surgical groups showed a small benefit over no treatment ( mean 29·4 points [ SD 11·9 ] , mean difference vs decompression 2·8 points [ 95 % CI 0·5–5·2 ] , p=0·0186 ; mean difference vs arthroscopy 4·2 [ 1·8–6·6 ] , p=0·0014 ) but these differences were not clinical ly important . There were six study -related complications that were all frozen shoulders ( in two patients in each group ) . Interpretation Surgical groups had better outcomes for shoulder pain and function compared with no treatment but this difference was not clinical ly important . Additionally , surgical decompression appeared to offer no extra benefit over arthroscopy only . The difference between the surgical groups and no treatment might be the result of , for instance , a placebo effect or postoperative physiotherapy . The findings question the value of this operation for these indications , and this should be communicated to patients during the shared treatment decision-making process . Funding Arthritis Research UK , the National Institute for Health Research Biomedical Research Centre , and the Royal College of Surgeons ( Engl and ) OBJECTIVES To compare the effect of grade d physiotherapeutic training of the rotator cuff versus arthroscopic subacromial decompression in patients with subacromial impingement . METHODS R and omised controlled trial with 12 months ' follow up in a hospital setting . Ninety consecutive patients aged 18 to 55 years were enrolled . Symptom duration was between six months and three years . All fulfilled a set of diagnostic criteria for rotator cuff disease , including a positive impingement sign . Patients were r and omised either to arthroscopic subacromial decompression , or to physiotherapy with exercises aim ing at strengthening the stabilisers and decompressors of the shoulder . Outcome was shoulder function as measured by the Constant score and a pain and dysfunction score . " Intention to treat " analysis was used , with comparison of means and control of confounding variables by general equation estimation analysis . RESULTS Of 90 patients enrolled , 84 completed follow up ( 41 in the surgery group , 43 in the training group ) . The mean Constant score at baseline was 34.8 in the training group and 33.7 in the surgery group . After 12 months the mean scores improved to 57.0 and 52.7 , respectively , the difference being non-significant . No group differences in mean pain and dysfunction score improvement were found . CONCLUSIONS Surgical treatment of rotator cuff syndrome with subacromial impingement was not superior to physiotherapy with training . Further studies are needed to qualify treatment choice decisions , and it is recommended that sample s are stratified according to disability level OBJECTIVE To determine distribution- and anchor-based minimal important difference ( MID ) estimates for four scores from the Functional Assessment of Cancer Therapy-Breast ( FACT-B ) : the breast cancer subscale ( BCS ) , Trial Outcome Index ( TOI ) , FACT-G ( the general version ) , and FACT-B. STUDY DESIGN AND SETTING We used data from a Phase III clinical trial in metastatic breast cancer ( ECOG study 1193 ; n=739 ) and a prospect i ve observational study of pain in metastatic breast cancer ( n=129 ) . One third and one half of the st and ard deviation and 1 st and ard error of measurement were used as distribution-based criteria . Clinical indicators used to determine anchor-based differences included ECOG performance status , current pain , and response to treatment . RESULTS FACT-B scores were responsive to performance status and pain anchors , but not to treatment response . By combining the results of distribution- and anchor-based methods , MID estimates were obtained : BCS=2 - 3 points , TOI=5 - 6 points , FACT-G=5 - 6 points , and FACT-B=7 - 8 points . CONCLUSION Distribution- and anchor-based estimates of the MID do show convergence . These estimates can be used in combination with other measures of efficacy to determine meaningful benefit and provide a basis for sample size estimation in clinical trials OBJECTIVE The purpose of this study was to determine the minimal important change ( MIC ) of improvement in the Constant-Murley score in patients with long-st and ing subacromial pain and in subgroups of patients with subacromial pain with and without rotator cuff ruptures . METHOD The MIC was estimated by the anchor-based MIC distribution method , which integrates an anchor- and distribution-based approach : the optimal cutoff point of the receiver operating characteristic curve ( MICROC ) and the 95 % limit cutoff point ( MIC95 % limit ) . The study population consisted of 93 patients included in a r and omized clinical trial evaluating the effect of a specific exercise strategy .  RESULTS The MICROC was found at a mean change of 17 points in the Constant-Murley score , which corresponds to a sensitivity of 91 % and a specificity of 79 % . The MIC95 % limit was found at a mean change of 24 points . In the subgroup analysis , the MICROC was found at a mean change of 19 points and the MIC95 % limit at 18 points in patients with an intact rotator cuff . In patients with rotator cuff ruptures , the MICROC was found at a mean change of 15 points and the MIC95 % limit at 30 points . CONCLUSION The Constant-Murley score is able to detect the MIC in individual patients with long-st and ing subacromial pain when the rotator cuff is intact . The estimated MIC values could be used as an indication for relevant changes in the Constant-Murley score in clinical practice and guide the clinician in how to interpret the results of specific treatments Background Arthroscopic subacromial decompression ( ASAD ) is a commonly performed surgical intervention for shoulder pain . The rationale is that removal of a bony acromial spur relieves symptoms by decompressing rotator cuff tendons passing through the subacromial space . However , the efficacy of this procedure is uncertain . The objective of this trial was to compare the efficacy and cost-effectiveness of ASAD in patients with subacromial pain using appropriate control groups , including placebo intervention . Methods / Design The trial is a three-group , parallel design , pragmatic , r and omised controlled study . The intervention content for each group ( ASAD , active monitoring with specialist re assessment ( AMSR ) and investigational shoulder arthroscopy only ( AO ) ) enables assessment of ( 1 ) the efficacy of the surgery against no surgery ; ( 2 ) the need for a specific component of the surgery — namely , removal of the bony spur ; and ( 3 ) quantification of the placebo effect . Concealed allocation was performed using a 1:1:1 r and omisation ratio and using age , sex , baseline Oxford Shoulder Score ( OSS ) and centre as minimisation criteria . The primary outcome measure is the OSS at 6 months post r and omisation .  A total of 300 patients recruited over 24 months from a minimum of 14 UK shoulder units over 24 months were required to detect a difference of 4.5 points on the OSS ( st and ard deviation , 9 ) with 90 % power and to allow for 15 % loss to follow-up . Secondary outcomes include cost-effectiveness , pain , complications and patient satisfaction . A substantial qualitative research component is included . The primary analysis will be conducted on the modified intention-to-treat analysis . Sensitivity analysis will be used to assess the robustness of the results with regard to the underlying assumptions about missing data using multiple imputation . Discussion This trial uses an innovative design to account for the known placebo effects of surgery , but it also will delineate the mechanism for any benefit from surgery . The investigational AO group is considered a placebo intervention ( not sham surgery ) , as it includes all components of subacromial decompression except the critical surgical element . Some discussion is also dedicated to the challenges of conducting placebo surgery trials . Trial registration sUK Clinical Research Network UKCRN12104 . Registered 22 May 2012.International St and ard R and omised Controlled Trial IS RCT N33864128 . Registered 22 June 2012 . Clinical Trials.gov NCT01623011 . Registered 15 June 2012 OBJECTIVE To establish a score threshold that constitutes a clinical ly relevant change for each domain of the Exp and ed Prostate Cancer Index Composite ( EPIC ) Short Form ( EPIC-26 ) . Although its use in clinical practice and clinical trials has increased worldwide , the clinical interpretation of this 26-item disease-specific patient-reported quality of life question naire for men with localized prostate cancer would be facilitated by characterization of score thresholds for clinical ly relevant change ( the minimally important differences [ MIDs ] ) . METHODS We used distribution- and anchor-based approaches to establish the MID range for each EPIC-26 domain ( urinary , sexual , bowel , and vitality/hormonal ) based on a prospect i ve multi-institutional cohort of 1201 men treated for prostate cancer between 2003 and 2006 and followed up for 3 years after treatment . For the anchor-based approach , we compared within-subject and between-subject score changes for each domain to an external " anchor " measure of overall cancer treatment satisfaction . RESULTS We found the bowel and vitality/hormonal domains to have the lowest MID range ( a 4 - 6 point change should be considered clinical ly relevant ) , whereas the sexual domain had the greatest MID values ( 10 - 12 ) . Urinary incontinence appeared to have a greater MID range ( 6 - 9 ) than the urinary irritation/obstruction domain ( 5 - 7 ) . CONCLUSION Using 2 independent approaches , we established the MIDs for each EPIC-26 domain . A definition of these MID values is essential for the research er or clinician to underst and when changes in symptom burden among prostate cancer survivors are clinical ly relevant Purpose Subacromial decompression is the st and ard surgical treatment of subacromial impingement syndrome . Unsatisfactory results have been reported for concomitant lesions as well as inadequate diagnosis . We sought to determine the predictive value of the preoperative examination for the results of arthroscopic subacromial decompression in impingement syndrome . Methods Forty-nine shoulder joints in 47 patients receiving arthroscopic subacromial decompression were prospect ively followed for a mean 3.7 ± 0.4 years . Prior to surgery , the impingement tests according to Neer , Hawkins – Kennedy ( in the neutral as well as abducted position ) , and the Jobe test ( empty can position ) were evaluated as well as the presence of a painful arc . The association between the presence of these sings , success of the operation , and improvement in Constant scores as well as WORC indices was analysed . Results Pre- to postoperative improvement in Constant scores as well as WORC indices was greater in case of a positive test result for every test studied . With the numbers available , significant greater improvements in Constant scores were observed only for patients with a positive Hawkins – Kennedy sign in the neutral position , Neer and Jobe tests , compared to patients with negative signs , respectively . No significant differences were observed for the improvement in WORC indices . Patients with at least four positive tests out of the five studied had greater improvement in Constant scores than patients with three or less positive test results . Five patients went on to receive subsequent shoulder surgery . There was no association between the necessity for revision surgery and the presence or absence of impingement signs . Conclusion The impingement tests according to Hawkins – Kennedy , Neer , and Jobe are valid predictors of outcome after subacromial decompression , as is the presence of multiple impingement tests . This study may aid in improving patient outcome and especially patient selection for subacromial decompression . Level of evidence Prognostic , Level Background Subacromial impingement syndrome ( SIS ) is the most frequently recorded shoulder disorder . When conservative treatment of SIS fails , a subacromial decompression is warranted . However , the best moment of referral for surgery is not well defined . Both early and late referrals have disadvantages – unnecessary operations and smaller improvements in shoulder function , respectively . This paper describes the design of a new interdisciplinary treatment strategy for SIS ( TRANSIT ) , which comprises rules to treat SIS in primary care and a well-defined moment of referral for surgery . Methods / Design The effectiveness of an arthroscopic subacromial decompression versus usual medical care will be evaluated in a r and omized controlled trial ( RCT ) . Patients are eligible for inclusion when experiencing a recurrence of SIS within one year after a first episode of SIS which was successfully treated with a subacromial corticosteroid injection . After inclusion they will receive injection treatment again by their general practitioner . When , after this treatment , there is a second recurrence within a year post-injection , the participants will be r and omized to either an arthroscopic subacromial decompression ( intervention group ) or continuation of usual medical care ( control group ) . The latter will be performed by a general practitioner according to the Dutch National Guidelines for Shoulder Problems . At inclusion , at r and omization and three , six and 12 months post-r and omization an outcome assessment will take place . The primary outcome measure is the patient-reported Shoulder Disability Question naire . The secondary outcome measures include both disease-specific and generic measures , and an economic evaluation . Treatment effects will be compared for all measurement points by using a GLM repeated measures analyses . Discussion The rationale and design of an RCT comparing arthroscopic subacromial decompression with usual medical care for subacromial impingement syndrome are presented . The results of this study will improve insight into the best moment of referral for surgery for SIS Background Psychologic factors are associated with pain and disability in patients with chronic shoulder pain . Recent research regarding the association of affective psychologic factors ( emotions ) with patients ’ pain and disability outcome after surgery disagrees ; and the relationship between cognitive psychologic factors ( thoughts and beliefs ) and outcome after surgery is unknown . Questions / purpose s ( 1 ) Are there identifiable clusters ( based on psychologic functioning measures ) in patients undergoing shoulder surgery  ? ( 2 ) Is poorer psychologic functioning associated with worse outcome ( American Shoulder and Elbow Surgeons [ ASES ] score ) after shoulder surgery ? Methods This prospect i ve cohort study investigated patients undergoing shoulder surgery for rotator cuff-related shoulder pain or rotator cuff tear by one of six surgeons between January 2014 and July 2015 . Inclusion criteria were patients undergoing surgery for rotator cuff repair with or without subacromial decompression and arthroscopic subacromial decompression only . Of 153 patients who were recruited and consented to participate in the study , 16 withdrew before data collection , leaving 137 who underwent surgery and were included in analyses . Of these , 124 ( 46 of 124 [ 37 % ] female ; median age , 54 years [ range , 21 - 79 years ] ) had a complete set of four psychologic measures before surgery  : Depression , Anxiety and Stress Scale ; Pain Catastrophizing Scale ; Pain Self-Efficacy Question naire ; and Tampa Scale for Kinesiophobia . The existence of clusters of people with different profiles of affective and cognitive factors was investigated using latent class analysis , which grouped people according to their pattern of scores on the four psychologic measures . Result ant clusters were profiled on potential confounding variables . The ASES score was measured before surgery and 3 and 12 months after surgery . Linear mixed models assessed the association between psychologic cluster membership before surgery and trajectories of ASES score over time adjusting for potential confounding variables . Results Two clusters were identified : one cluster ( 84 of 124 [ 68 % ] ) had lower scores indicating better psychologic functioning and a second cluster ( 40 of 124 [ 32 % ] ) had higher scores indicating poorer psychologic functioning . Accounting for all variables , the cluster with poorer psychologic functioning was found to be independently associated with worse ASES score at all time points ( regression coefficient for ASES : before surgery -9 [ 95 % confidence interval { CI } , -16 to -2 ] , p = 0.011 ) ; 3 months after surgery -15 [ 95 % CI , -23 to -8 ] , p < 0.001 ) ; and 12 months after surgery -9 [ 95 % CI , -17 to -1 ] , p = 0.023 ) . However , both clusters showed improvement in ASES score from before to 12 months after surgery , and there was no difference in the amount of improvement between clusters ( regression coefficient for ASES : cluster with poorer psychologic function 31 [ 95 % CI , 26 - 36 ] , p < 0.001 ) ; cluster with better psychologic function 31 [ 95 % CI , 23 - 39 ] , p < 0.001 ) . Conclusions Patients who scored poorly on a range of psychologic measures before shoulder surgery displayed worse ASES scores at 3 and 12 months after surgery . Screening of psychologic factors before surgery is recommended to identify patients with poor psychologic function . Such patients may warrant additional behavioral or psychologic management before proceeding to surgery . However , further research is needed to determine the optimal management for patients with poorer psychologic function to improve pain and disability levels before and after surgery . Level of Evidence Level II , therapeutic study Introduction Arthroscopic subacromial decompression ( ASD ) is the most commonly performed surgical intervention for shoulder pain , yet evidence on its efficacy is limited . The rationale for the surgery rests on the tenet that symptom relief is achieved through decompression of the rotator cuff tendon passage . The primary objective of this superiority trial is to compare the efficacy of ASD versus diagnostic arthroscopy ( DA ) in patients with shoulder impingement syndrome ( SIS ) , where DA differs only by the lack of subacromial decompression . A third group of supervised progressive exercise therapy ( ET ) will allow for pragmatic assessment of the relative benefits of surgical versus non-operative treatment strategies . Methods and Analysis Finnish Subacromial Impingement Arthroscopy Controlled Trial is an ongoing multicentre , three-group r and omised controlled study . We performed two-fold concealed allocation , first by r and omising patients to surgical ( ASD or DA ) or conservative ( ET ) treatment in 2:1 ratio and then those allocated to surgery further to ASD or DA in 1:1 ratio . Our two primary outcomes are pain at rest and at arm activity , assessed using visual analogue scale ( VAS ) . We will quantify the treatment effect as the difference between the groups in the change in the VAS scales with the associated 95 % CI at 24 months . Our secondary outcomes are functional assessment ( Constant score and Simple shoulder test ) , quality of life ( 15D and SF-36 ) , patient satisfaction , proportions of responders and non-responders , reoperations/treatment conversions , all at 2 years post-r and omisation , as well as adverse effects and complications .  We recruited a total of 210 patients from three tertiary referral centres . We will conduct the primary analysis on the intention-to-treat basis . Ethics and Dissemination The study was approved by the Institutional Review Board of the Pirkanmaa Hospital District and duly registered at Clinical Trials.gov . The findings of this study will be disseminated widely through peer- review ed publications and conference presentations . Trial registration number NCT00428870 ; Pre- results
Our review provides anchor-based MID estimates , as well as a rating of their credibility , for PROMs for patients with shoulder conditions .
The MID estimates inform the interpretation for a linked systematic review and guideline addressing subacromial decompression surgery for shoulder pain , and could also prove useful for authors addressing other interventions for shoulder problems .
OBJECTIVES To identify credible anchor-based minimal important differences ( MIDs ) for  patient-reported outcome measures  ( PROMs ) relevant to a BMJ Rapid Recommendations addressing subacromial decompression surgery for shoulder pain .