We found no negative impact of diabetes diagnosis at the level of component scores for mental HRQoL (MCS scores), but examination of the individual SF-36 subscales that combine to form this component revealed significant differences in the ILS arm for the Social Functioning and Role-Emotional subscales following diagnosis. Both of these subscales ask respondents to report the extent to which physical or mental health status interferes with their ability to engage in social tasks or perform these tasks at expected levels (e.g., Did not do work or other activities as carefully as usual?). Consistent with previous studies [31,32], this finding suggests that the MCS component scores