Impact of Alzheimer's Disease on Caregiver Questionnaire: internal consistency, convergent validity, and test-retest reliability of a new measure for assessing caregiver burden.

BACKGROUND: There is a lack of validated instruments to measure the level of burden of Alzheimer's disease (AD) on caregivers. The Impact of Alzheimer's Disease on Caregiver Questionnaire (IADCQ) is a 12-item instrument with a seven-day recall period that measures AD caregiver's burden across emotional, physical, social, financial, sleep, and time aspects. Primary objectives of this study were to evaluate psychometric properties of IADCQ administered on the Web and to determine most appropriate scoring algorithm. METHODS: A national sample of 200 unpaid AD caregivers participated in this study by completing the Web-based version of IADCQ and Short Form-12 Health Survey Version 2 (SF-12v2™). The SF-12v2 was used to measure convergent validity of IADCQ scores and to provide an understanding of the overall health-related quality of life of sampled AD caregivers. The IADCQ survey was also completed four weeks later by a randomly selected subgroup of 50 participants to assess test-retest reliability. Confirmatory factor analysis (CFA) was implemented to test the dimensionality of the IADCQ items. Classical item-level and scale-level psychometric analyses were conducted to estimate psychometric characteristics of the instrument. Test-retest reliability was performed to evaluate the instrument's stability and consistency over time. RESULTS: Virtually none (2%) of the respondents had either floor or ceiling effects, indicating the IADCQ covers an ideal range of burden. A single-factor model obtained appropriate goodness of fit and provided evidence that a simple sum score of the 12 items of IADCQ can be used to measure AD caregiver's burden. Scales-level reliability was supported with a coefficient alpha of 0.93 and an intra-class correlation coefficient (for test-retest reliability) of 0.68 (95% CI: 0.50-0.80). Low-moderate negative correlations were observed between the IADCQ and scales of the SF-12v2. CONCLUSIONS: The study findings suggest the IADCQ has appropriate psychometric characteristics as a unidimensional, Web-based measure of AD caregiver burden and is supported by strong model fit statistics from CFA, high degree of item-level reliability, good internal consistency, moderate test-retest reliability, and moderate convergent validity. Additional validation of the IADCQ is warranted to ensure invariance between the paper-based and Web-based administration and to determine an appropriate responder definition.

Challenges Facing Early Phase Trials Sponsored by the National Cancer Institute: An Analysis of Corrective Action Plans to Improve Accrual.

Accruing patients in a timely manner represents a significant challenge to early phase cancer clinical trials. The NCI Cancer Therapy Evaluation Program analyzed 19 months of corrective action plans (CAP) received for slow-accruing phase I and II trials to identify slow accrual reasons, evaluate whether proposed corrective actions matched these reasons, and assess the CAP impact on trial accrual, duration, and likelihood of meeting primary scientific objectives. Of the 135 CAPs analyzed, 69 were for phase I trials and 66 for phase II trials. Primary reasons cited for slow accrual were safety/toxicity (phase I: 48%), design/protocol concerns (phase I: 42%, phase II: 33%), and eligibility criteria (phase I: 41%, phase II: 35%). The most commonly proposed corrective actions were adding institutions (phase I: 43%, phase II: 85%) and amending the trial to change eligibility or design (phase I: 55%, phase II: 44%). Only 40% of CAPs provided proposed corrective actions that matched the reasons given for slow accrual. Seventy percent of trials were closed to accrual at time of analysis (phase I = 48; phase II = 46). Of these, 67% of phase I and 70% of phase II trials met their primary objectives, but they were active three times longer than projected. Among closed trials, 24% had an accrual rate increase associated with a greater likelihood of meeting their primary scientific objectives. Ultimately, trials receiving CAPs saw improved accrual rates. Future trials may benefit from implementing CAPs early in trial life cycles, but it may be more beneficial to invest in earlier accrual planning. Clin Cancer Res; 22(22); 5408-16. ©2016 AACRSee related commentary by Mileham and Kim, p. 5397.