investigating the quality control of laboratory information

clinical laboratory results play an important role in helping physicians in diagnosis and treatment. in view of the direct effect of the working methods on the quality of data in the laboratory, quality control of data and results in the biochemistry ward of laboratory includes taking into account all the factors and variables relating to all the pre-analytical, analytical and post-analytical steps at this ward. the objective of this study was to examine the quality control of data and results in the biochemistry departments of hospital laboratories in universities of medical sciences in tehran.current study was a descriptive research, and 40 biochemistry laboratories in universities of medical sciences in tehran constituted the settings of the study. data were collected by a checklist and a questionnaire using observation and interview. using the checklist, 33 effective factors in the pre-analytical step; 18 effective factors in the analytical step and 8 effective factors in post-analytical step were examined. the questionnaire included questions relating to biochemical factors in the laboratories, while the factors affecting the quality of the results were examined by using checklist. data from questions and observations were analyzed by using descriptive statistics and by determining the absolute and relative frequencies.results showed that in all settings of the study, 58%, 68% and 87% of the factors affecting the pre-analytical, analytical and post-analytical data and results were taken into consideration respectively. however, the biochemistry directors remarked that they considered 77% and 89% of the first two groups of factors respectively, and the third groups of factors were considered only by observation.according to the findings by the checklists, sufficient attention  was paid to 58% of the factors effective on pre-analytical data quality (identifying the patient; labeling the sample while collecting the sample; etc.), 68% of the factors effective on analytical data quality (analyzing the samples during the 1 to 4 hours following the collection of the samples; using control samples for evaluating the operation of instruments once in every 8 hours; etc.) and 87% of the factors effective on the post-analytical data quality (legibility of the hand-written reports; similarity of the hand-written reports to the typewritten report, in terms of patient id data record; etc.) while there is no enough attention paid to other factors in pre-analytical step (preparing the patient; paying attention to the physiological changes of the patient’s body; etc.), analytical step (availability of written guidelines for performing certain work where the samples are analyzed; calibrating the instruments according to the standard program; etc.) and post-analytical step (precision in recording distinguishing features in real values). also, by comparing the findings obtained using the two tools, it can be found out that the findings do not match each other in certain factors and that the amount of findings obtained from the questionnaire is more than the findings obtained from the checklists.