Evaluating home environments of persons with dementia: interrater reliability and validity of the Home Environmental Assessment Protocol (HEAP)

Purpose: This article reports on an interrater reliability and preliminary validity study of an investigator-developed tool, the Home Environmental Assessment Protocol (HEAP) for use in homes of persons with dementia. Method: The HEAP consists of 192 items that are summed into separate indices representing the number of hazards, adaptations, and level of clutter and comfort in eight areas of the home. Interrater reliability was examined among four raters, two environmental experts and two non-experts, who observed 22 dementia households. Results: The Kappa statistic was used to evaluate agreement level for each measured item and found that agreement ranged from slight to almost perfect. Intraclass correlations (ICCs), were used to evaluate agreement level for indices. The hazard index in each room ranged from fair (0.36) to moderate (0.66) for all raters. For the adaptation, clutter and comfort indices in each room, ICCs ranged from 0.51 to 0.90 for all raters. Agreement level between expert and non-expert raters differed minimally for all indices. Adaptations to dining rooms (r = -0.080, p = 0.001), kitchens (r = -0.52, p = 0.02) and bedrooms (r = -0.76, p = 0.001) were associated with patient deficits such that more adaptations were made in homes of dependent persons. Low Mini-Mental Status Examination scores were associated with fewer hazards, more adaptations, and less clutter. Conclusion: Findings show that both experts and non-expert raters use the HEAP consistently. Also, measured attributes are related to cognitive and functional status in the expected direction.