patients experience preventable harm from medical errors , mistakes and teamwork failures ( 1 ) . it is a guiding factor in daily care and a central issue in healthcare ( 3 , 4 ) . for example , in iran , it is not taught to medical personnel , traditionally ( 6 ) . however , preventable adverse events are common in developed and developing countries ( 7 ) . there has been a growing awareness of the measures and cost of incidence in two decades ago ( 8) . for example , childbirth s mortality and morbidity highlight the importance of learning from events ( 10 ) . it is necessary to revisit patient safety , changes , remained challenges , emerging new problems , and effect of health care in the quality and safety of healthcare ( 11 ) . patients perspective is patients beliefs and attitudes in the field of preventing and controlling errors and the risk of error occurring ( 13 ) . a patient engaging with safety is the most benefit of strengthening a relationship with physicians and nurses ( 14 ) . patients misperceptions result in emerging obstacles in the environment that patients themselves have to manage ( 13 ) . the patients negative perspective into hospital s patient safety may reversely conduce to incongruity in referrals and follow - up , petitions and allegations concerning jeopardizing patient s life . there are many individual , environmental and organizational factors for not accurately evaluating healthcare , quality and patient safety level in hospitals ( 16 ) . acording to the findings of australian patient safety report ( 2001 ) , public hospitals survey in kerman , iran ( 2006 ) , educational hospital survey in izmir , turkey ( 2006 ) , patient safety survey in urmia , iran ( 2010 ) , urmia patient safety survey ( 2012 ) , patient safety survey in isfahan , iran ( 2012 ) and iranian patient safety survey ( 2012 ) , the premier factors are as follows : age , gender , marital status , education , insurance coverage , employment status , period of referring to physician and the date of latest hospitalization ( 17 ) . even so , patients perspective have excluded in the construction of clinical governance and health - care reforms . it requires decreasing the imbalance of information and power between patients and healthcare professionals . addressing this problem therefore , it is necessary to notify , realize , modify or remove the cause and effect of the negative perspective ( 18 ) . the general aims of this study were : 
 - to determine patient safety level in tehran university of medical sciences general hospitals from patients perspective- to determine the contributory factors on patients perspective . - to determine patient safety level in tehran university of medical sciences general hospitals from patients perspective - to determine the contributory factors on patients perspective . this study had a cross - sectional design carried out in a period of six - month  from may 2011 to november 2011 . the study populations were inpatients in the clinical wards that had the experience of hospitalizing . first step : the sample size was calculated by using the following formula : 
 n = z1-/22p(1-p)d2on the ground that no researches have been done so far , the favorable perception of involvement in treatment decisions and patient safety was considered 50% ( p=0.5 ) . the sample size for each treatment decision and perceptions of safety were calculated 180 in the first step considering to the confident interval 95% ( =0.05 ) and maximum deviation 7.5% ( d=0.075 ) . second step : according to clark s study ( 2001 ) , the minimum r that influenced various factors was 0.6 ( 19 ) . therefore , the desirable sample size was calculated 300 . in the spring of 2011 , the list of six general hospitals affiliated to tehran university of medical sciences ( tums) clinical wards were prepared . the numbers of clinical wards in each hospital were 120 as follows : 
 - imam hospital : 39 wards ( icu & ccu : 13 , surgery , transplant , obstetrics and gynecology : 13 , internal medicine , infectious diseases , ear , nose and throat , general : 13)- baharlou hospital : 16 wards ( icu & ccu : 5 , surgery , transplant , obstetrics and gynecology : 5 , internal medicine , infectious diseases , ear , nose and throat , general : 6)- shariati hospital : 37 wards ( icu & ccu : 12 , surgery , transplant , obstetrics and gynecology : 12 , internal medicine , infectious diseases , ear , nose and throat , general : 13)- ziaian hospital : 13 wards ( icu & ccu : 4 , surgery , transplant , obstetrics and gynecology : 4 , internal medicine , infectious diseases , ear , nose and throat , general : 5)- amiralam hospital : 7 wards ( icu & ccu : 1 , surgery , transplant , obstetrics and gynecology : 1 , internal medicine , infectious diseases , ear , nose and throat , general : 5)- sina hospital : 8 wards ( icu & ccu : 3 , surgery , transplant , obstetrics and gynecology : 3 , internal medicine , infectious diseases , ear , nose and throat , general : 2 ) . - imam hospital : 39 wards ( icu & ccu : 13 , surgery , transplant , obstetrics and gynecology : 13 , internal medicine , infectious diseases , ear , nose and throat , general : 13 ) - baharlou hospital : 16 wards ( icu & ccu : 5 , surgery , transplant , obstetrics and gynecology : 5 , internal medicine , infectious diseases , ear , nose and throat , general : 6 ) - shariati hospital : 37 wards ( icu & ccu : 12 , surgery , transplant , obstetrics and gynecology : 12 , internal medicine , infectious diseases , ear , nose and throat , general : 13 ) - ziaian hospital : 13 wards ( icu & ccu : 4 , surgery , transplant , obstetrics and gynecology : 4 , internal medicine , infectious diseases , ear , nose and throat , general : 5 ) - amiralam hospital : 7 wards ( icu & ccu : 1 , surgery , transplant , obstetrics and gynecology : 1 , internal medicine , infectious diseases , ear , nose and throat , general : 5 ) - sina hospital : 8 wards ( icu & ccu : 3 , surgery , transplant , obstetrics and gynecology : 3 , internal medicine , infectious diseases , ear , nose and throat , general : 2 ) . eventually , the stratified random sampling method was used . the 120 wards were divided into three groups as : 
 - group 1 : intensive care unit ( icu and ccu ) ( 38 wards);- group 2 : surgery , transplant , obstetrics and gynecology ( 38 wards);- group 3 : internal medicine , infectious diseases , ear , nose and throat , general ( 44 wards).300 samples were proportionally divided between 3 groups . the numbers of samples in each group were as : 
 - group 1 : 95- group 2 : 95- group 3 : 110 - group 1 : intensive care unit ( icu and ccu ) ( 38 wards ) ; - group 2 : surgery , transplant , obstetrics and gynecology ( 38 wards ) ; - group 3 : internal medicine , infectious diseases , ear , nose and throat , general ( 44 wards ) . the numbers of wards in each group were : 
 - group 1 : 5 wards- group 2 : 5 wards- group 3 : 6 wards . finally , the sample was selected as follows : 
 - group 1 : imam ccu , baharlou ccu , shariati ccu , general imam icu , ziaian ccu and post ccu.- group 2 : imam surgery , amiralam surgery , sina general surgery , shariati general surgery , ziaian surgery.- group 3 : imam internal , amiralam internal , baharlou internal , shariati internal pulmonary , shariati internal , ziaian internal . - group 1 : imam ccu , baharlou ccu , shariati ccu , general imam icu , ziaian ccu and post ccu . - group 2 : imam surgery , amiralam surgery , sina general surgery , shariati general surgery , ziaian surgery . - group 3 : imam internal , amiralam internal , baharlou internal , shariati internal pulmonary , shariati internal , ziaian internal . library and internet research the questionnaire was developed by clark in 2001 ( 17 ) to assess patients opinions about patient safety issues , medical error , and event reporting . it includes 37 items in 4 sections as follows : demographic characteristics ( eight questions ) , general information regarding the doctors and hospitals ( six questions ) , participation in treatment decisions ( 12 questions ) and patient safety ( 11 questions ) . the five - level likert scale was employed for the responses as follows : strongly disagree ( 1 score ) , disagree ( 2 score ) , neither ( 3 score ) , agree ( 4 score ) and strongly agree ( 5 score ) . therefore , the participation s level was evaluated as follows : 
 - 1236 score : low- 3660 score : high . therefore , the patient safety s level was as follows : - 2641 score : intermediate the questionnaire was translated into farsi . then , both the translated questionnaire and the original one were handed to some experts in order to revise it . after that , the comprehensibility of the survey was tested on 20 patients from the study population who had not been included in our sample . the reliability coefficient of the questionnaire was calculated 0.78 . according to patients perspective , we prepared the final version of the farsi questionnaire after altering some questions and eliminating irrelevant questions . the questionnaire was developed by clark in 2001 ( 17 ) to assess patients opinions about patient safety issues , medical error , and event reporting . it includes 37 items in 4 sections as follows : demographic characteristics ( eight questions ) , general information regarding the doctors and hospitals ( six questions ) , participation in treatment decisions ( 12 questions ) and patient safety ( 11 questions ) . the five - level likert scale was employed for the responses as follows : strongly disagree ( 1 score ) , disagree ( 2 score ) , neither ( 3 score ) , agree ( 4 score ) and strongly agree ( 5 score ) . therefore , the participation s level was evaluated as follows : 
 - 1236 score : low- 3660 score : high . therefore , the patient safety s level was as follows : - 2641 score : intermediate the questionnaire was translated into farsi . then , both the translated questionnaire and the original one were handed to some experts in order to revise it . after that , the comprehensibility of the survey was tested on 20 patients from the study population who had not been included in our sample . , we prepared the final version of the farsi questionnaire after altering some questions and eliminating irrelevant questions . participants demographic characteristics were as follows : 60% were female , and the rests ( 40% ) were male . 20% , 23% and 20% were 2418 , 4435 and 55 years - old people , respectively . the ethnicity of 32% , 24.3% and 21% was azeri , kurd and fars , sequentially . health insurance , social security insurance and other insurances coverage were 37% , 23% and 25.7% , sequentially . patient safety was evaluated high , intermediate and low by 60% , 14% and 26% of patients , respectively . patient safety variables included : demographic variables ( including age , gender , education , ethnicity , marital status , insurance type , employment status and income statues ) , period of referring to family physician or general practitioner , the date of latest medical consultation , the number of hospitalizations in the past year , the date of latest hospitalization , hospital s type , exposure to adverse events and patient participation in treatment decisions . tables 1 and 2 show the results of linear regression and multivariate logistic regression , respectively . according to the table 1 , patients socio - demographic , medical and hospitalized variables affecting on the hospital s patient safety score were as follows : age , gender , ethnicity , marital status , education , insurance coverage , employment statues , period of referring to family physician , or general practitioner , the date of latest hospitalization , the date of latest exposure to adverse events , participation in treatment decisions ( p<0.1 ) . for adjusting possible problematical factors and achieving independent factors , affecting variables imported in the final multivariate logistic regression model by a stepwise method . the most important variables affecting on the hospital s patient safety score were as follows : education , employment status and marital status . education , employment status and marital status decreased odds ratio of dedicating high score to hospital s patient safety , 0.014 , 0.32 and 0.19 times , respectively . it was meaning that the unmarried or educated or employed individuals tended to score patient safety lower than others . according to the findings , patient safety was evaluated high by the most of patients ( 60% ) hospitalized in tums s general hospitals . considering to their perspective , much attention has been paid to patient safety in health care , the registration and the examination of safety incidents , particularly in hospitals . it is in concordance with sheikh beiklou s survey in urmia s public and private hospitals . according to the findings , patient safety was ranked high ( 56% ) from the patients perspective ( 17 ) . poor attention to patient safety results in errors , low quality of care , and increases the length of stay ( 5).there are a number of risk areas in which errors and risks are more likely to occur . therefore , patients perspective provides a rich source of data in looking at how patient s power impacts upon safety in organizational contexts ( 3 ) . education , employment status and marital status are the premier factors affecting on evaluating patient safety in hospitals . it is in concordance with florin s survey in 2006 . according to the findings , the disparate perspective was pertinent to age , marital and social status including example education , employment ( 21 ) . it is consistent with the findings of other surveys : clark in australia s private and general hospitals ( 19 ) , larsson et al . ( 22 ) , in kerman s public hospitals , iran ( 23 ) , in izmir s educational hospitals , turkey ( 24 ) , and schwappach and et al . nowadays , the consumers are more conscious in healthcare market . because educated people have more risk - assessment ability they rapidly conceive whether providers perform their duties , the services are concordant , effective and patient - centered , there is  do it right  culture in healthcare organization or not . it is consistent with the findings of other reviews : oskouiee and zare in tabriz s educational hospitals , iran ( 17 ) , leventhal ( 25 ) , ozdemir et al . in izmir s educational hospitals , turkey ( 24 ) , and ghaffari and rakhshande in iran ( 16 ) it is consistent with the findings of other reports : clark in australia s general and private hospitals ( 19 ) and ozdemir and et al in izmir s educational hospitals , turkey ( 24 ) . according to the findings of  patient safety survey in urmia hospitals  , mousavi et al . emphasized that patients perspective is the most important criterion for appraising patient safety in hospitals . it is pertinent to some of patients characteristics such as marital status ( 26 ) . it is because of communicating with others , increasing awareness and understanding issues such as safety . the employed or married patients inquire into disease , medical process and healthcare organizations from communicating or consulting with their colleagues , friends and family members . patients perspective is the most important catalyst to the emergence of a safety movement in healthcare over the last decade ( 3 ) . understanding the patients perspective is a pivotal way of generating knowledge about the processes involved in harm . it must nt ignore in the adoption of a  no - blame culture in patient safety . however , tums s general hospitals are enough safe from patients perspective , patient safety should be improved . the contributory factors , such as education , employment and marital status , were conclusive to claim that these factors were predicting patients perspective in safety matters . in clinical governance , contributing patients perspective to the improvement of patient safety reforms is critical in generating new models of good practice . health care organizations can go beyond mainstream frameworks for quality and patient safety improvement by create higher value for patients perspective . this study has two research methods also have limitations : the lack of cooperation of some hospitals to do research and patients unwillingness to fill the questionnaire . 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 .
backgroundit is important to focus on creating opportunities for patients participation at all levels of health systems in order to promote their ability to improve patient safety and quality of services . 
 the general aim of this study was to determine patient safety level in tehran university of medical sciences ( tums ) general hospitals , tehran , iran from patients perspective and to determine the contributory factors on their perspective.methods:this was a cross - sectional study . in the spring 2011 
 , the list of clinical departments of the six general hospitals affiliated to tums was obtained through the website of tums . by using stratified random sampling , 
 the sample size was calculated 300 patients . 
 data were collected by using a structured questionnaire and its validity and reliability were acceptable . 
 descriptive statistics , linear regression and logistic regression were used for analyzing the data.results:totally , 60% of patients were female . 
 patient safety was evaluated high by 60% of respondents . 
 the unmarried or educated or employed individuals tend to score lower than others.conclusion:tumss general hospitals are enough safe from patients perspective , patient safety should be improved . in clinical governance , contributing patients perspective to the improvement of patient safety reforms is critical in generating new models of good practice .