Quality Assurance

This section contains the following:


Introduction 

The success of any clinical trial depends on the quality of the data collected.  Ensuring good quality data requires developing extensive and detailed quality assurance procedures such as those for monitoring the clinical centres; and those for assuring quality of data handling and processing in the coordinating centre.  As in all aspects of clinical trials, a quality control program requires attention to detail and careful planning.  This program should include plans for data checking (how much will be checked by whom, and by what method); audit trails (detailed log showing which data have been changed, the reason for any change, who made the change and when); and source verification procedures (how much data will be checked against source document).  There should be a written description of the quality control program within the Manual of Operations.  

During the planning of data collection and management, a number of decisions must be made regarding quality assurance procedures, here are some questions you might like to think about:




Back to top


Things to consider 


Back to top



Additional resources

  Checklist for data checks

This checklist has been contributed by Barbara Farrell who prepared it for the third version of the Trial Management Guide


Back to top


  Checklist for double data entry

This checklist has been contributed by Barbara Farrell who prepared it for the third version of the Trial Management Guide.


Back to top


  Checklist for missing and inconsistent data

This checklist has been contributed by Barbara Farrell who prepared it for the third version of the Trial Management Guide.


Back to top



Further reading

Baigent C, Harrell FE, Buyse M, et al. Ensuring trial validity by data quality assurance and diversification of monitoring methods. Clinical Trials 2008; 5:49-55.

Neaton JD, Duchene AG, Svendsen KH, et al. An examination of the efficiency of some quality assurance methods commonly employed in clinical trials. Statistics in  Medicine 1990;9:115–124

Williams OD. A framework for the quality assurance of clinical data. Clinical Pharmacology and therapeutics 1979: 24; 700-702

Knatterud GL. Methods of quality control and of continuous audit procedures for controlled clinical trials. Controlled clinical trials 1981:1;327-332

Hosking JD, Rochon J. A comparison of techniques for detecting and preventing key-field errors. American Statistical Association, 1982, pp 82-87

Mullooly JP. The effects of data entry errors: an analysis of partial verification. Computational Biomedical research 1990; 23: 259-267

Pocock SJ. Clinical Trials: A Practical Approach. John Wiley and Sons, Chichester, 1983.

Duley L and Farrell B.  Clinical Trials. London: BMJ Books, 2002.


Back to top     


This page was last updated December 2008