Yiyue Lou

The concordance of survey reports and Medicare claims in a nationally representative longitudinal cohort of older adults.

Background:Concordance between survey reports and claims data is not well established. We compared them for disease histories, preventative, and other health services use in a large, nationally representative sample of older Medicare beneficiaries with special attention given to evaluating age, aging, memory, and respondent status effects. Methods:Baseline (1993) and biennial follow-up data (through 2010) from the Survey on Assets and Health Dynamics among the Oldest-Old were linked to Medicare claims from 1991 to 2010, for 4910 participants yielding 19,556 person-periods. Concordance was measured by simple, weighted, and prevalence and bias-adjusted &kgr;, and Lin’s concordance statistics. Generalized estimating equation negative binomial models were used to predict the summary counts of concordant reports, survey underreports, and survey overreports. Results:Concordance was highly variable overall, unacceptably low for arthritis and physician visits, and less than substantial for angina, heart disease, hypertension, and outpatient surgery. Generalized estimating equation negative binomial models revealed reductions in reporting accuracy (more underreporting and overreporting) associated with both age (interindividual) and aging (intraindividual) effects, countervailing memory effects on concordance due to less underreporting but more overreporting, and countervailing proxy-respondent effects on concordance due to less underreporting but more overreporting. Conclusions:Further research should explore whether these findings are time or cohort bound, address the potential heterogeneity of the proxy-respondent effects based on the reason for and relationship of the proxy to the target person, and evaluate the effects of a broader spectrum of performance-based cognitive abilities. In the interim, the significant predictors identified here should be included in future studies.

Cognitive function and the concordance between survey reports and Medicare claims in a nationally representative cohort of older adults.

Background:While age-related cognitive decline may affect all stages in the response process—comprehension, retrieval, judgment, response selection, and response reporting—the associations between objective cognitive tests and the agreement between self-reports and Medicare claims has not been assessed. We evaluate those associations using the Survey on Assets and Health Dynamics among the Oldest Old (AHEAD). Methods:Eight waves of reinterviews (1995–2010) were linked to Medicare claims for 3661 self-respondents yielding 12,313 person-period observations. Cognitive function was measured by 2 episodic memory tests (immediate and delayed recall of 10 words) and 1 mental status test (backward counting, dates, and names). Survey reports on 12 diseases and 4 health services were mapped to Medicare claims to derive counts of concordant reports, underreports, and overreports, as were the numbers of hospital episodes and physician visits. GEE negative binomial and logistic regression models were used. Results:Better mental status was associated with more concordant reporting and less underreporting on disease history and the number of hospital episodes. Better mental status and delayed word recall were associated with more concordant reporting and less underreporting on health services use. Better delayed recall was significantly associated with less underreporting on the number of physician visits. These associations were not appreciably altered by adjustment for demographic characteristics, socioeconomic status, self-rated health, or secular trends. Conclusion:We recommend that future surveys of older adults include an objective measure of mental status (rather than memory), especially when those survey reports cannot be verified by access to Medicare claims or chart review.

Activating Patients With a Tailored Bone Density Test Results Letter and Educational Brochure: the PAADRN Randomized Controlled Trial

In cross-sectional studies, patient activation has been associated with better health behaviors, health outcomes, and health-care experiences. Moreover, tailored interventions have led to clinically meaningful improvements in patient activation, as well as health outcomes over time. We tested whether a tailored patient-activation letter communicating bone mineral density (BMD) test results plus an educational brochure improved patient activation scores and levels at 12 and 52 wk post-baseline as the mechanism leading to enhanced bone healthcare. In a randomized, controlled, double-blinded, multicenter pragmatic clinical trial, we randomized 7749 patients ≥50 yr old and presenting for BMD testing at 3 medical centers in the United States between February 2012 and August 2014. The outcome measures were patient activation scores and levels based on 6 items taken from the Patient Activation Measure (PAM) that were administered at the baseline, 12-wk, and 52-wk follow-up interviews. Mean age was 66.6 yr, 83.8% were women, and 75.3% were Non-Hispanic-Whites. Overall, PAM activation scores improved from 58.1 at baseline to 76.4 by 12 wk (p < 0.001) and to 77.2 (p = 0.002) by 52 wk post-baseline. These improvements, however, were not significantly different between the intervention and usual care groups (18.7 vs 18.1, p = 0.176, at 12 wk) in intention-to-treat analyses. PAM activation scores and levels substantially improved at 12 wk and 52 wk, but no differences were observed in these improvements between the intervention and usual care groups. These null findings may have occurred because the tailoring focused on the patients BMD and fracture risk results, rather than on the patients BMD and fracture risk results as well as the patients baseline PAM activation scores or levels.

Racial Differences and Disparities in Osteoporosis-related Bone Health: Results From the Paadrn Randomized Controlled Trial

Background: Determining whether observed differences in health care can be called disparities requires persistence of differences after adjustment for relevant patient, provider, and health system factors. We examined whether providing dual-energy x-ray absorptiometry (DXA) test results directly to patients might reduce or eliminate racial differences in osteoporosis-related health care. Design, Subjects, and Measures: We analyzed data from 3484 white and 1041 black women who underwent DXA testing at 2 health systems participating in the Patient Activation after DXA Result Notification (PAADRN) pragmatic clinical trial (ClinicalTrials.gov NCT-01507662) between February 2012 and August 2014. We examined 7 outcomes related to bone health at 12 weeks and 52 weeks post-DXA: (1) whether the patient correctly identified their DXA baseline results; (2) whether the patient was on guideline-concordant osteoporosis pharmacotherapy; (3) osteoporosis-related satisfaction; (4) osteoporosis knowledge; (5 and 6) osteoporosis self-efficacy for exercise and for diet; and (7) patient activation. We examined whether unadjusted differences in outcomes between whites and blacks persisted after adjusting for patient, provider, and health system factors. Results: Mean age was 66.5 years and 29% were black. At baseline black women had less education, poorer health status, and were less likely to report a history of osteoporosis (P<0.001 for all). In unadjusted analyses black women were less likely to correctly identify their actual DXA results, more likely to be on guideline-concordant therapy, and had similar patient activation. After adjustment for patient demographics, baseline health status and other factors, black women were still less likely to know their actual DXA result and less likely to be on guideline-concordant therapy, but black women had greater patient activation. Conclusions: Adjustment for patient and provider level factors can change how racial differences are viewed, unmasking new disparities, and providing explanations for others.

A pilot study among older adults of the concordance between their self-reports to a health survey and spousal proxy reports on their behalf

BackgroundProxy respondents are frequently used in health surveys, and the proxy is most often the spouse. Longstanding concerns linger, however, about the validity of using spousal proxies, especially for older adults. The purpose of this pilot study was to evaluate the concordance between self-reports and spousal proxy reports to a standard health survey in a small convenience sample of older married couples.MethodsWe used the Seniors Together in Aging Research (STAR) volunteer registry at the University of Iowa to identify and consent a cross-sectional, convenience sample of 28 married husband and wife couples. Private, personal interviews with each member of the married couple using a detailed health survey based on the 2012 Health and Retirement Study (HRS) instrument were conducted using computer assisted personal interviewing software. Within couples, each wife completed the health survey first for herself and then for her husband, and each husband completed the health survey first for himself and then for his wife. The health survey topics included health ratings, health conditions, mobility, instrumental activities of daily living (IADLs), health services use, and preventative services. Percent of agreement and prevalence and bias adjusted kappa statistics (PABAKs) were used to evaluate concordance.ResultsPABAK coefficients indicated moderate to excellent concordance (PABAKs >0.60) for most of the IADL, health condition, hospitalization, surgery, preventative service, and mobility questions, but only slight to fair concordance (PABAKs = −0.21 to 0.60) for health ratings, and physician and dental visits.ConclusionsThese results do not allay longstanding concerns about the validity of routinely using spousal proxies in health surveys to obtain health ratings or the number of physician and dental visits among older adults. Further research is needed in a nationally representative sample of older couples in which each wife completes the health survey first for herself and then for her husband, each husband completes the health survey first for himself and then for his wife, and both spouses’ Medicare claims are linked to their health survey responses to determine not just the concordance between spousal reports, but the concordance of those survey responses to the medical record.

Estimation of causal effects in clinical endpoint bioequivalence studies in the presence of intercurrent events: noncompliance and missing data

ABSTRACT In clinical endpoint bioequivalence (BE) studies, the primary analysis for assessing equivalence between a generic and an innovator product is based on the observed per-protocol (PP) population (usually completers and compliers). However, missing data and noncompliance are post-randomization intercurrent events and may introduce selection bias. Therefore, PP analysis is generally not causal. The FDA Missing Data Working Group recommended using “causal estimands of primary interest.” In this paper, we propose a principal stratification causal framework and co-primary causal estimands to test equivalence, which was also recommended by the recently published ICH E9 (R1) addendum to address intercurrent events. We identify three conditions under which the current PP estimator is unbiased for one of the proposed co-primary causal estimands – the “Survivor Average Causal Effect” (SACE) estimand. Simulation shows that when these three conditions are not met, the PP estimator is biased and may inflate Type 1 error and/or change power. We also propose a tipping point sensitivity analysis to evaluate the robustness of the current PP estimator in testing equivalence when the sensitivity parameters deviate from the three identified conditions, but stay within a clinically meaningful range. Our work is the first causal equivalence assessment in equivalence studies with intercurrent events.