Patient-reported outcomes questionnaire compliance in Cancer Cooperative Group Trials (Alliance N0992)

Background/Aims: The use of patient-reported outcomes in clinical trials is a focal point for research and policy. Non-compliance with planned questionnaires and missing data can threaten both internal validity and generalizability. This retrospective analysis was conducted to determine the extent of, and characteristics associated with, missing patient-reported outcomes. Methods: Study characteristics, patient characteristics and adverse events, and reasons for non-compliance were compiled from 14 closed Alliance for Clinical Trials in Oncology, Mayo Clinic Cancer Center, or Mayo Clinic Cancer Research Consortium clinical trials. Compliance rates were calculated for each patient using the number of booklets completed while the patient was on trial divided by the number of booklets the patient was expected to complete. Frequency counts and summary statistics were compiled. Logistic regression techniques were employed. Results: The 1640 included patients had a median age of 58 years and were mostly White (90.8%) and female (73.8%). Compliance rates per study ranged from 84.7% to 97.2%. The primary endpoint of overall compliance rate was 93.1%. A total of 1267 patients were compliant. Those non-compliant were slightly older (mean = 58.6 vs 57.5, p = 0.03) and had different types of cancers (p < 0.01). There were no differences in compliance according to tumor status (p = 0.66), clinical stage (p = 0.81), baseline quality of life (p = 0.42 for ≥8 vs <8 and p = 0.12 for ≥6 vs <6), or maximum adverse event grade incidence (p = 0.33 for grade 2+ incidence and p = 0.36 for grade 3+ incidence). Reasons for non-compliance included patient refusal (N = 136), booklet not administered to patient (N = 199), no clinic visit at the scheduled time for booklet completion (N = 40), and at-home-completed booklet not returned (N = 224). Logistic regression indicates gender (p < 0.01), race (p < 0.01), performance score (p = 0.02), dose delay status (p = 0.01), and incidence of grade 3 or higher adverse event (p = 0.03) were correlates of compliance. Conclusion: Patient-reported outcomes have successfully been implemented into Alliance and Mayo Clinic trials with high rates of patient compliance. Further improvement in compliance can be made with staff commitment and education. Patients are typically non-compliant only when the task at hand is burdensome, unclear, or logistically challenging. Existing tracking systems used for the other trial outcomes should be utilized to ensure successful capture of patient-reported outcomes.