it has a special importance in health economics , and imposes higher costs on the health system compared to the other health system components ( 1 , 2 ) .
hospitals are the main consumer of resources in any health sector thus ; improvement of their efficiency is the main way to decrease the hospital costs ( 3 ) .
thus , providing criteria for evaluation of hospital performance and productivity is important ( 2 , 4 ) . these features are doubled , especially in developing countries , considering their economic structure and extreme vulnerability to deal with fluctuations in currency and commodity markets . in a way , that full response to the needs of consumers in this sector , even in the most advanced countries , seems to be out of reach ( 5 , 6 ) .
hence , the iranian hospitals are no exception from this issue . in this situation , the hospitals managers strategies for reducing the costs and increasing the productivity is necessary ( 7 ) .
productivity is one of the important concepts in assessing the performance of organization over time .
productivity expresses a kind of relationship between the amount of the produced goods or services and the amount of resources , which is consumed in producing goods and services .
therefore , productivity is a measure that shows the relationship between outputs and inputs ( 8) .
productivity indicators show improvement or reduction in performance ( 9 ) . the information obtained from productivity sub - indicators
are used to identify the problems of unites , define the strategies , and in case of need , make change in the staff behaviors ( 10 ) .
several techniques to assessment hospital efficiency and productivity are usually considered either parametric or non - parametric . ( 11 ) .
non - parametric methods such as data envelopment analysis are the most popular ( 12 ) .
this study was performed to determine the productivity rate of hospitals by using data envelopment analysis technique in ahvaz , iran .
this is a cross sectional study in which the panel data were used in a 4 year period from 2007 to 2010 .
the research was implemented in 17 teaching and non - teaching hospitals of ahvaz county , southern iran . as five hospitals did not agree to participate in this study ; and finally 12 hospitals were assessed .
variables were selected based on the experts opinions and previous studies ( 1 , 13 , 14 ) . the set of input and output variables that we have used in this study are similar to those applied in other studies ( 1517 ) .
the input measures included are number of nurses , number of occupied beds and number of physicians .
the output measures included are number of outpatients and inpatients , average of hospital stay , and number of major operations data were collected by studying the medical records and documents of the hospitals retrospectively .
data envelopment analysis technique and the malmquist indices with an input - orientation approach , was used to analyze the data and estimation of productivity .
we selected input - orientation approach and variable returns to scale ( vrs ) model for data analysis . in input - orientation approach , decision - making units ( dmus ) can change their inputs ( 18 , 19 ) . when the productivity and efficiency measurement are based on the input - orientation approach ( minimizing the production factors ) , a value of more than one show productivity decline and a value of less than one show productivity growth ( 1 , 7 ) .
data envelopment analysis technique and the malmquist indices with an input - orientation approach , was used to analyze the data and estimation of productivity .
we selected input - orientation approach and variable returns to scale ( vrs ) model for data analysis . in input - orientation approach , decision - making units ( dmus ) can change their inputs ( 18 , 19 ) . when the productivity and efficiency measurement are based on the input - orientation approach ( minimizing the production factors ) , a value of more than one show productivity decline and a value of less than one show productivity growth ( 1 , 7 ) .
as noted in table 1 , j hospital has the highest value and h hospital has the lowest value of total productivity changes .
therefore , the range of changes of productivity for hospitals was from 0.785 to 1.127 , and j and h hospitals had the best and worst performance respectively .
k hospital had the maximum value of changes in technical , technological , managerial and scale efficiency .
h hospital had the lowest technical and scale efficiency changes , g hospital had the lowest technological efficiency changes and i hospital had the minimum management performance changes .
six hospitals ( 50% ) had a value lower than 1 , which represents an increase in total productivity between 2007 and 2010 .
five hospitals ( 41.66 % ) had a value higher than 1 , which represents a decrease in total productivity and one hospital ( 8.33 % ) had a value equal to 1 which reflects stagnation in total productivity changes . efficiency and total productivity change by hospital type ( teaching and non - teaching hospital ) according to the table 2 ,
the average of total productivity was 1.024 , which reflects a decrease in productivity changes by 2.4% in study period .
the average total productivity change of all factors in the year 2008 was more than 1 , which shows that the level of productivity of hospitals has been decreased in this year .
changes in technological performance had a negative impact on the rate of productivity and had the main role in reducing productivity .
efficiency and productivity change in three years - period ( 200 - 8 - 2010 ) as noted in table 3 , mean of the productivity change had a significant difference among teaching and non - teaching hospitals ( p=0.001 ) in 2009 and had not significant differences in other years .
in general , there was no significant difference in average of productivity changes between teaching and non - teaching hospitals .
the results showed that the productivity of hospitals over the years 2007 - 2010 has increased and had an ascending trend .
however , the average of total productivity was 1.024 , which shows 2.4% reduction ; and changes in technological performance had the highest impact on decrease in value of total productivity .
different values for total factors productivity have been reported in different researches in iran and other countries .
a study in iran showed that just fewer than 60% of all hospitals at were technically efficient and therefore they were non - product because efficiency of units has direct association with productivity trend ( 2 ) .
( 8) in a similar study reported increase in the productivity of 31 regional hospitals in taiwan .
the average of productivity changes in the taiwan s hospitals was ( 0.874 ) was lower than average of productivity changes in our study .
one way to increase technical efficiency is decrease of length of stay and increase of hospital size .
it should be noted productivity change is affected scale efficiency changes , technological performance and managerial performance ( 13 , 15 ) .
( 22 ) reported that the average productivity of the hospitals has declined by 3.3% in ardebil and the technological efficiency changes had the most negative effects on total productivity .
evaluation of the causes of these effects can be helpful in improvement of the total productivity .
technological improvements play an important role in increasing the productivity of larger hospitals ( 23 ) .
findings of our study showed that despite improvement in productivity trend of hospitals , the average of productivity of hospitals not improved ; this result can be used as a warning in order to make better use of existing resources . some hospitals ( a
, b , c , g , h and i ) used resources the more appropriate which can be considered as a model for other hospitals ( d , e , f , i , j , k and l ) . in hospitals
that the main cause of low productivity is changes in technology efficiency , it seems that lack of enough familiarity of managers with the advanced hospital technologies , lack of equipment and inappropriate use of technology in diagnosis , care and treatment , are the main causes ( 22 ) .
second , medical record system is manual and third , dea software has technical limitations .
in the f and k hospitals the main cause of the low productivity is changes in technical efficiency therefore mangers must use inputs ( doctors , nurses and beds ) efficiently and increase the outputs . in hospitals
e that the main cause of low productivity is negative changes of scale efficiency therefore managers must improve the scale efficiency .
finally , according to results of this study , decrease of technological efficiency had the highest negative impact on average of total productivity of hospitals .
therefore , hospital managers and policy makers can use economic of scale methods including : optimizing size of hospitals , increase of production volume and decrease of the length of stay ( by means of discharge process optimizing ) for productivity improvement of hospitals .
ethical issues ( including plagiarism , informed consent , misconduct , data fabrication and/or falsification , double publication and/or submission , redundancy , etc . ) have been completely observed by the authors .
 abstractbackgroundthis study aimed to measure the hospital productivity using data envelopment analysis ( dea ) technique and malmquist indices.methodsthis is a cross sectional study in which the panel data were used in a 4 year period from 2007 to 2010 . 
 the research was implemented in 12 teaching and non - teaching hospitals of ahvaz county . 
 data envelopment analysis technique and the malmquist indices with an input - orientation approach , was used to analyze the data and estimation of productivity . 
 data were analyzed using the spss.18 and deap.2 software.resultssix hospitals ( 50% ) had a value lower than 1 , which represents an increase in total productivity and other hospitals were non - productive . 
 the average of total productivity factor ( tpf ) was 1.024 for all hospitals , which represents a decrease in efficiency by 2.4% from 2007 to 2010 . 
 the average technical , technologic , scale and managerial efficiency change was 0.989 , 1.008 , 1.028 , and 0.996 respectively . 
 there was not a significant difference in mean productivity changes among teaching and non - teaching hospitals ( p>0.05 ) ( except in 2009 years).conclusionproductivity rate of hospitals had an increasing trend generally . 
 however , the total average of productivity was decreased in hospitals . besides , between the several components of total productivity , variation of technological efficiency had the highest impact on reduce of total average of productivity . 
Introduction
Materials and Methods
Data collection
Data Analysis
Results
Discussion
Conclusions
Ethical considerations