Are Social Deprivation and Low Traditional Health Literacy Associated With Higher PROMIS CAT Completion in Orthopaedic Surgery?
Authors: Litvak Audrey L. , Lin Nicholas A. , Hynes Kelly K. , Strelzow Jason A. , Conti Mica Megan A. , Stepan Jeffrey G. 
Published: September 2023

Abstract

Background
The Patient-Reported Outcomes Measurement Information System® (PROMIS®) may be used to assess an individual patient’s perspective of their physical, mental, and social health through either standard or computer adaptive testing (CAT) patient questionnaires. These questionnaires are used across disciplines; however, they have seen considerable application in orthopaedic surgery. Patient characteristics associated with PROMIS CAT completion have not been examined within the context of social determinants of health, such as social deprivation or health literacy, nor has patient understanding of the content of PROMIS CAT been assessed.

Questions/purposes
(1) What patient demographics, including social deprivation, are associated with completion of PROMIS CAT questionnaires? (2) Is health literacy level associated with completion of PROMIS CAT questionnaires? (3) Do patients with lower health literacy have a higher odds of completing PROMIS CAT without fully understanding the content?

Methods
Between June 2022 and August 2022, a cross-sectional study was performed via a paper survey administered to patients at a single, urban, quaternary academic medical center in orthopaedic subspecialty clinics of foot and ankle, trauma, and hand/upper extremity surgeons. We considered all English-speaking patients aged 18 or older, including those with limited reading and/or writing abilities, as eligible provided they received an iPad in clinic to complete the PROMIS CAT questionnaire as part of their routine standard clinical care or they completed the questionnaire via a patient portal before the visit. In all, 946 patients were considered eligible during the study period and a convenience sample of 36% (339 of 946) of patients was approached for inclusion due to clinic time constraints. Fifteen percent (52 of 339) declined to participate, leaving 85% (287 of 339) of patients for analysis here. Median (range) age of study participants was 49 years (35 to 64). Fifty-eight percent (167 of 287) of study participants self-identified as non-Hispanic Black or African American and 26% (75 of 287) as non-Hispanic White. Even proportions were observed across education levels (high school graduate or less, 29% [82 of 287]; some college, 25% [73 of 287]; college graduate, 25% [71 of 287]; advanced degree, 20% [58 of 287]). Eighteen percent (52 of 287) of patients reported an annual income bracket of USD 0 to 13,000, and 17% (48 of 287) reported more than USD 120,000. Forty-six percent (132 of 287) of patients worked full-time, 21% (59 of 287) were retired, and 23% (66 of 287) were unemployed or on disability. The primary outcome of interest was self-reported PROMIS CAT questionnaire completion grouped as: fully completed, partially completed, or no part completed. Overall, self-reported PROMIS CAT questionnaire completion proportions were: 80% (229 of 287) full completion, 13% (37 of 287) partial completion, and 7% (21 of 287) no part completed. We collected the National Area Deprivation Index (ADI) score and the Brief Health Literacy Screening Tool (BRIEF) as part of the study survey to associate with level of completion. Additionally, patient understanding of PROMIS CAT was assessed through Likert-scaled responses to a study survey question that directly asked whether the patient understood all of the questions on the PROMIS CAT questionnaire. Responses to this question may have been limited by social desirability bias, and hence may overestimate how many individuals genuinely understood the questionnaire content. However, the benefit of this approach was it efficiently allowed us to estimate the ceiling effect of patient comprehension of PROMIS CAT and likely had a high degree of specificity for detecting lack of comprehension.

Results
ADI score adjusted for age was not associated with PROMIS CAT completion (partial completion OR 1.00 [95% CI 0.98 to 1.01]; p = 0.72, no part completed OR 1.01 [95% CI 0.99 to 1.03]; p = 0.45). Patients with lower health literacy scores, however, were more likely to not complete any part of their assigned questionnaires than patients with higher scores (no part completed OR 0.85 [95% CI 0.75 to 0.97]; p = 0.02). Additionally, 74% (26 of 35) of patients who did not fully understand all of the PROMIS CAT questionnaire questions still fully completed them—hence, 11% (26 of 229) of all patients who fully completed PROMIS CAT did not fully understand the content. Among patients self-reporting full completion of PROMIS CAT with health literacy data (99% [227 of 229]), patients with inadequate/marginal health literacy were more likely than patients with adequate health literacy to not fully understand all of the questions (21% [14 of 67] versus 8% [12 of 160], OR 3.26 [95% CI 1.42 to 7.49]; p = 0.005).

Conclusion
Within an urban, socioeconomically diverse, orthopaedic patient population, health literacy was associated with PROMIS CAT questionnaire completion. Lower health literacy levels increased the likelihood of not completing any part of the assigned PROMIS CAT questionnaires. Additionally, patients completed PROMIS CAT without fully understanding the questions. This indicates that patient completion does not guarantee comprehension of the questions nor validity of their scores, even more so among patients with low health literacy. This is a substantive concern for fidelity of data gathered from PROMIS CAT.

Clinical Relevance
Clinical implementation of the PROMIS CAT in orthopaedic populations will benefit from further research into health literacy to increase questionnaire completion and to ensure that patients understand the content of the questions they are answering, which will increase the internal validity of the outcome measure.