Developing Patient-Reported Outcome Measures to Assess Side Effects of Cancer Treatment [Internet]

Background: Although patient questionnaires are commonly used to assess health care experiences (eg, satisfaction with care), patient-reported outcome performance measures (PRO-PMs) assessing symptoms and physical functioning have not been part of quality assessment in oncology.

Objective: To develop and test PRO-PMs for use during chemotherapy.

Methods:

1. Aim 1: We interviewed 124 stakeholders to identify key symptoms to test as PRO-PMs and potential risk adjustment variables.

2. Aim 2: We conducted a structured literature review to identify prevalent symptoms. We combined the results from interviews and the literature review through expert consensus into a final list of symptoms. Then, we evaluated existing PRO-PMs assessing identified symptoms.

3. Aim 3: We enrolled patients actively receiving chemotherapy at 6 cancer centers (in California, Connecticut, Florida, Minnesota, North Carolina, and Texas). Each patient completed PRO-PM items at home between 5 and 15 days after initiation of a therapy cycle.

Patients chose to complete the questionnaire online, by an automated telephone system, or on paper, and it was available in English, Spanish, and Mandarin. We defined feasibility as at least 75% of patients completing the PRO questionnaire. We developed practice-level PRO-PM specifications for each symptom individually (eg, proportion of patients at a practice with well-controlled symptom [eg, pain]) and for multisymptom summary measures. To account for variation in case mixes across cancer centers, we risk-adjusted every measure using hierarchical logistic regression models predicting the odds of high symptom burden, controlling for cancer type, age, sex, and race. For the multisymptom measures, optimal cutoffs were identified as those that maximized validity (correlation with physical functioning) and reliability (ability to accurately differentiate performance across providers) while remaining clinically actionable.

Results: Interviews in aim 1 included patients with cancer in active treatment (n = 56); primary caregivers (n = 21); patient investigators (n = 5); clinicians without clinic administrative responsibilities (n = 11); health care administrators (n = 16, of whom 12 were also clinicians); and national experts, including clinicians (n = 15, of whom 5 were also clinicians). We recruited patients, caregivers, clinicians, and health care administrators from the 6 cancer centers and identified experts nationally. Among patients with cancer, 48% were women, 34% were aged ≥65 years, 14% were Black/African American, 8% were Asian, and 20% had a high school education or less. Common cancer types included genitourinary (32%), gastrointestinal (27%), breast (21%), and lung (20%). Caregiver relationships were typically a spouse, partner, or adult child.

In aim 2, we combined a literature review with interview results from aim 1 to refine a final list of symptoms to test, as follows: gastrointestinal symptoms (nausea, vomiting, constipation, diarrhea), sleep issues, depression, anxiety, pain, neuropathy, and shortness of breath. Although fatigue and appetite loss were acknowledged by the stakeholders as being important, we eliminated these symptoms because they are not sufficiently clinically treatable. Stakeholder recommendations for risk adjustment variables to test empirically included insurance status, cancer type, age, sex, and difficulty paying bills.

In aim 3, a total of 653 patients enrolled, of whom 607 completed the questionnaire (93%). Specifically, 470 of 607 (77%) completed the PRO questionnaire without a reminder call, and another 14% completed it after a staff member called. Most (>95%) participants found the PRO questions to be easy to understand and complete. When questionnaires were aggregated to the cancer center level, 1 cancer center descriptively appeared to perform better than others across measures, and 1 appeared to perform relatively worse, with the other 4 sites grouped similarly. Adjusting for cancer type and age had a modest effect on site-level scores. Adjustment variables for insurance status, sex, and difficulty paying bills were not significant in models and were thus removed. Empirical testing showed that combining the individual PRO-PM items for pain, nausea, and diarrhea was possible, with an optimal cutoff score of 0 to 4 vs 5 to 12 and with higher scores indicating greater symptom burden. The optimal cutoff scores for the 10-item measure were 0 to 14 vs 15 to 40. Summary PRO-PMs numerically differentiated between cancer centers but did not meet the recommended reliability threshold.

Conclusions: Patients, caregivers, clinicians, national experts, and other stakeholders agree that performance measures based on how patients feel and function would be an important addition for payers to use in evaluating the quality of care provided by health care systems and provider groups. PRO-PMs can be feasibly captured at home during systemic therapy and are acceptable to patients. PRO-PMs may add meaningful information to evaluate quality of care, but more data are needed to establish the reliability and validity of these PRO-PMs before adopting them into performance-based oncology payment models.

Limitations: Testing occurred at 6 sites among more than 600 patients, and further testing would strengthen generalizability. Additional data are also needed to meet recommended reliability thresholds. Such testing is planned.