An assessment of factors associated with quality of randomized controlled trials for smoking cessation

// Hong Fan 1, 2 , Fujian Song 3 , Hai Gu 1 , Jianming Wang 2, 4 , Guizhen Jia 2 , Moyuan Lu 2 , Jiao Qian 2 , Lei Wang 2 , Jiemiao Shen 2 , Zhewen Ren 2 1 Center for Health Policy and Management Research, Nanjing University, Nanjing, P.R.China 2 Department of Social Medicine and Health Education, School of Public Health, Nanjing Medical University, Nanjing, P.R.China 3 Department of Population Health and Primary Care, Norwich Medical School, University of East Anglia, Norwich, UK 4 Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, P.R.China Correspondence to: Hong Fan, email: fanhong365@163.com Fujian Song, email: Fujian.Song@uea.ac.uk Hai Gu, email: ghai1008@nju.edu.cn Keywords: smoking cessation, quality, randomized controlled trials Received: April 13, 2016      Accepted: July 10, 2016      Published: July 20, 2016 ABSTRACT To reduce smoking-related diseases, a research priority is to develop effective interventions for smoking cessation, and evidence from randomized controlled trials (RCTs) is usually considered to be the most valid. However, findings from RCTs may still be misleading due to methodological flaws. This study aims to assess the quality of 1083 RCTs of smoking cessation interventions in 41 relevant Cochrane Systematic Reviews (CSRs). Logistic regression analysis was performed to identify significant variables associated with the quality of RCTs. It was found that evidence for smoking cessation from RCTs was predominantly from high income countries, and the overall quality was high in only 8.6% of the RCTs. High quality RCTs tended to have a larger sample size, to be more recently published, and conducted in multiple countries belonging to different income categories. In conclusion, the overall quality of RCTs of smoking cessation interventions is far from perfect, and more RCTs in less developed countries are required to generate high grade evidence for global tobacco control. Collaboration between researchers in developed and less developed countries should be encouraged.