THE TYPE AND QUALITY OF RANDOMIZED CONTROLLED TRIALS (RCTS) PUBLISHEDIN UK PUBLIC-HEALTH JOURNALS

Background Randomized controlled trials (RCTs) are increasingly being used to evaluate the effectiveness of health care interventions. Syste matic reviews of RCTs form the basis of the Cochrane Collaboration, wh ich aims to synthesize all RCTs concerned with the provision of health care. This paper reports the quantity and methodological quality of R CTs published in five UK public health journals, which were searched a s part of a planned register of RCTs in public health. Methods Five jo urnals were hand searched: The International Journal of Epidemiology, Health Trends, Journal of Public Health Medicine, Public Health and Th e Journal of Epidemiology and Community Health. All RCTs were identifi ed and their methodological characteristics reviewed. Results Ninety-o ne trials were identified from the five journals. A wide variety of to pics were covered, the most common being prevention strategies (46 per cent of the trials). Although the actual number of reports of RCTs pu blished increased over time, there was no detectable improvement in th e quality of reports. The aspect of bias most well controlled was cont rol of bias at entry (randomization), in 83 (91 per cent) of trials. H owever, even in these trials details about the process of randomizatio n were poor. Conclusion These trials will form the basis of a register of RCTs in public health. The diversity of topics covered illustrates the broad-based nature of public health. For this reason, many other RCTs relevant to the practice of public health are likely to be found in non-public-health journals.