Test-Retest Reliability and Minimal Detectable Change of Four Cognitive Tests in Community-Dwelling Older Adults

BACKGROUND

Cognitive test-retest reliability measures can be used to evaluate meaningful changes in scores.

OBJECTIVE

This analysis aimed to develop a comprehensive set of test-retest reliability values and minimal detectable change (MDC) values for a cognitive battery for community-dwelling older individuals in Australia and the U.S., for use in clinical practice.

METHODS

Cognitive scores collected at baseline and year 1, in the ASPirin in Reducing Events in the Elderly clinical trial were used to calculate intraclass correlation coefficients (ICC) for four tests: Modified Mini-Mental State examination (3MS), Hopkins Verbal Learning Test-Revised (HVLT-R), single-letter Controlled Oral Word Association Test (COWAT-F), and Symbol Digit Modalities Test (SDMT). 16,956 participants aged 70 years and over (65 years and over for U.S. minorities) were included. ICCs were used to calculate MDC values for eight education and ethno-racial subgroups.

RESULTS

All four cognitive tests had moderate (ICC > 0.5) to good (ICC > 0.7) test-retest reliability. ICCs ranged from 0.53 to 0.63 (3MS), 0.68 to 0.77 (SDMT), 0.56 to 0.64 (COWAT-F), 0.57 to 0.69 (HVLT-R total recall), and 0.57 to 0.70 (HVLT-R delayed recall) across the subgroups. MDC values ranged from 6.60 to 9.95 (3MS), 12.42 to 15.61 (SDMT), 6.34 to 8.34 (COWAT-F), 8.13 to 10.85 (HVLT-R total recall), and 4.00 to 5.62 (HVLT-R delayed recall).

CONCLUSION

This large cohort of older individuals provides test-retest reliability and MDC values for four widely employed tests of cognitive function. These results can aid interpretation of cognitive scores and decline instead of relying on cross-sectional normative data alone.

Is the presence of mild to moderate cognitive impairment associated with self-report of non-cancer pain? A cross-sectional analysis of a large population-based study

CONTEXT

Research, guidelines, and experts in the field suggest that persons with cognitive impairment report pain less often and at a lower intensity than those without cognitive impairment. However, this presupposition is derived from research with important limitations, namely, inadequate power and lack of multivariate adjustment.

OBJECTIVES

We conducted a cross-sectional analysis of the Canadian Study of Health and Aging to evaluate the relationship between cognitive status and pain self-report.

METHODS

Cognitive status was assessed using the Modified Mini-Mental State Examination. Pain was assessed using a 5-point verbal descriptor scale. For analysis, responses were dichotomized into "no pain" vs. "any pain" and "pain at a moderate or higher intensity" vs. "pain not at a moderate or higher intensity." Additional predictors included demographics, physical function, depression, and comorbidity.

RESULTS

Of 5,703 eligible participants, 306 (5.4%) did not meet inclusion criteria, leaving a total of 5,397, of whom 876 (16.2%) were cognitively impaired. In the unadjusted analysis, significantly more cognitively intact (n=2,541; 56.2%) than cognitively impaired (n=456; 52.1%; P=0.03) participants reported noncancer pain. There was no significant difference in the proportion of cognitively intact (n=1,623; 35.9%) and impaired (n=329; 37.6%; P=0.36) participants who reported pain to be at moderate or higher intensity. In multivariate analyses, cognitively impaired participants did not have lower odds of reporting any noncancer pain (odds ratio [OR]=0.83 [0.68-1.01]; P=0.07) or pain at a moderate or higher intensity (OR=0.95 [0.78-1.16]; P=0.62).

CONCLUSION

Non-cancer pain was equally prevalent in people with and without cognitive impairment, which contrasts with the currently held opinion that cognitively impaired persons report noncancer pain less often and at a lower intensity.