Reporting and analysis of missing participant continuous data in randomized controlled trials (LOST-IT-II): a systematic survey

Oral
2015 Vienna
Zhang Y1, Flórez ID2, Colunga L3, Abu Bakar Aloweni F4, Alexander Kennedy S5, Li A1, Craigie S6, Zhang S7, Agarwal A8, Cruz Lopes L9, Devji T10, Wiercioch W11, J. Riva J12, Wang M11, Jin X11, Fei Y13, Alexander P1, Morgano GP11, Zhang Y11, Carrasco-Labra A14, Kahale LA15, Meyre D16, Akl E17, Schünemann HJ11, Thabane L1, Guyatt G11
1Department of Clinical Epidemiology and Biostatistics, McMaster University, Canada
2Universidad de Antioquia, Medellin and McMaster University , Colombia, Canada
3Hospital Civil de Guadalajara, "Fray Antonio Alcalde", México
4Singapore General Hospital, Singapore
5Department of Medicine, McMaster University, Canada
6Michael G DeGroote Institute for Pain Research and Care, McMaster University, Canada
7Medical Affairs, GSK , Canada
8Faculty of Medicine, University of Toronto, Canada
9Universidade de Sorocaba, São Paulo, Brazil
10Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada, Canada
11Department of Medicine and Clinical Epidemiology and Biostatistics, McMaster University, Canada
12Department of Family Medicine, McMaster University, Canada
13Beijing University of Chinese Medicine, McMaster University, China, Canada
14Department of Medicine and Clinical Epidemiology and Biostatistics, McMaster University; Evidence-Based Dentistry Unit Faculty of Dentistry, Universidad de Chile Santiago, Chile , Chile
15Department of Internal Medicine, American University of Beirut, Lebanon, Lebanon
16Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada; Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada, Canada
17Clinical Epidemiology Unit and Center for Systematic Reviews in Health Policy and Systems Research (SPARK), American University of Beirut, Lebanon

Background:

Missing participant data (MPD) can bias trial results and conclusions if the missingness is associated with the occurrence of the outcome of interest. No study has summarized the reporting and analytic approaches of MPD that authors have used for continuous outcomes in randomized controlled trials (RCTs).

Objective:

Our objectives are to assess: 1) how authors report MPD for continuous outcomes; 2) the analytic methods used for primary analysis and sensitivity analysis to address MPD; and 3) the impact of these sensitivity analyses on the conclusions.

Method:

We are conducting a systematic survey of RCTs published in 2014 in core medical journals. We include RCTs reporting at least one patient-important outcome analyzed as a continuous variable. We randomly sample RCTs aiming at a sample size of 200. We will calculate the proportion of RCTs that explicitly reported whether MPD occurred, percentage of randomized participants with MPD for the continuous outcome, the methods used to handle MPD in the primary and sensitivity analyses, and how often the conclusions are interpreted considering the sensitivity analyses conducted and whether consideration of MPD changes the conclusion. We will conduct regression analyses with independent variables general trial characteristics (e.g. type of funding, type of intervention) and methodological trial characteristics (e.g. allocation concealment, length of follow-up), to establish factors associated with reporting, analysis, and conclusions.

Conclusion:

Our methodological survey will have important implications for both trialists and users of trial evidence in interpretation of the findings from RCTs with MPD on continuous outcomes.