TY - JOUR
T1 - Multiple outcomes and analyses in clinical trials create challenges for interpretation and research synthesis
AU - Mayo-Wilson, Evan R
AU - Fusco, Nicole
AU - Li, Tianjing
AU - Dickersin, Kay
AU - Hong, Hwanhee
AU - Canner, Joseph K.
N1 - Funding Information:
Funding: Supported by contract ME 1303 5785 from the Patient-Centered Outcomes Research Institute (PCORI) and a fund established at Johns Hopkins for scholarly research on reporting biases by Greene LLP. The funders were not involved in the design or conduct of the study, article preparation, or the decision to submit the article for publication.
Publisher Copyright:
© 2017 The Authors
PY - 2017/6
Y1 - 2017/6
N2 - Objective To identify variations in outcomes and results across reports of randomized clinical trials (RCTs). Study Design and Setting Eligible RCTs examined gabapentin for neuropathic pain and quetiapine for bipolar depression, reported in public (e.g., journal articles) and nonpublic (e.g., clinical study reports) sources by 2015. We prespecified outcome domains. From each source, we collected “outcomes” (i.e., domain, measure, metric, method of aggregation, and time point); “treatment effect” (i.e., outcome plus the methods of analysis [e.g., how missing data were handled]); and results (i.e., numerical contrasts of treatment and comparison groups). We assessed whether results included sufficient information for meta-analysis. Results We found 21 gabapentin (68 public, 6 nonpublic reports) and seven quetiapine RCTs (46 public, 4 nonpublic reports). For four (gabapentin) and seven (quetiapine) prespecified outcome domains, RCTs reported 214 and 81 outcomes by varying four elements. RCTs assessed 605 and 188 treatment effects by varying the analysis of those outcomes. RCTs reported 1,230 and 661 meta-analyzable results, 305 (25%) and 109 (16%) in public reports. Conclusion RCTs included hundreds of outcomes and results; a small proportion were in public reports. Trialists and meta-analysts may cherry-pick what they report from multiple sources of RCT information.
AB - Objective To identify variations in outcomes and results across reports of randomized clinical trials (RCTs). Study Design and Setting Eligible RCTs examined gabapentin for neuropathic pain and quetiapine for bipolar depression, reported in public (e.g., journal articles) and nonpublic (e.g., clinical study reports) sources by 2015. We prespecified outcome domains. From each source, we collected “outcomes” (i.e., domain, measure, metric, method of aggregation, and time point); “treatment effect” (i.e., outcome plus the methods of analysis [e.g., how missing data were handled]); and results (i.e., numerical contrasts of treatment and comparison groups). We assessed whether results included sufficient information for meta-analysis. Results We found 21 gabapentin (68 public, 6 nonpublic reports) and seven quetiapine RCTs (46 public, 4 nonpublic reports). For four (gabapentin) and seven (quetiapine) prespecified outcome domains, RCTs reported 214 and 81 outcomes by varying four elements. RCTs assessed 605 and 188 treatment effects by varying the analysis of those outcomes. RCTs reported 1,230 and 661 meta-analyzable results, 305 (25%) and 109 (16%) in public reports. Conclusion RCTs included hundreds of outcomes and results; a small proportion were in public reports. Trialists and meta-analysts may cherry-pick what they report from multiple sources of RCT information.
KW - Clinical trials
KW - Meta-analysis
KW - Outcomes
KW - Selective outcome reporting
KW - Systematic reviews
UR - http://www.scopus.com/inward/record.url?scp=85020419684&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85020419684&partnerID=8YFLogxK
U2 - 10.1016/j.jclinepi.2017.05.007
DO - 10.1016/j.jclinepi.2017.05.007
M3 - Review article
C2 - 28529187
AN - SCOPUS:85020419684
SN - 0895-4356
VL - 86
SP - 39
EP - 50
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
ER -