This study aims to examine the longitudinal effects of a small-scale nursing home model on the change rates of psychological outcomes by comparing green house (GH) and traditional nursing home residents.

A total of 242 residents (93 GH and 149 traditional home residents) who resided at the home least 6 months from admission. Four minimum dataset assessments every six months from admission were included. The main psychological outcomes were depressive mood, and social engagement. The main independent variable was the facility type that the resident resided in: a GH or traditional unit. Age, gender, ADL function, and cognitive function at admission were controlled in the model. A zero-inflated Poisson (ZIP) growth curve model was utilized to compare change rates of two psychological outcomes between the two groups taking into account many zero counts of two outcome measures.

A rate of increase in depressive symptoms for GH home residents was higher than that of traditional home residents (β = 0.135, p-value = 0.025). GH home residents had a lower rate of increase of the probability of “not being socially engaged” over time compared to traditional home residents (β = −0.274, p-value = 0.010).

The GH nursing home model had a longitudinal effect on increasing the probability of residents’ social engagement over time, but also increasing the recognition of depressive symptoms compared to traditional nursing homes.