Data for the current study were from a nation-wide cross-sectional survey of mental health literacy conducted in Singapore from March 2014 to April 2015. It adopted a disproportionate stratified sampling design with 12 strata by age (18–34, 35–49, 50–65) and ethnicity groups (Chinese, Malay, Indian, and other ethnic groups). A probability sample was randomly selected via a registry that maintains the names and socio-demographic characteristics such as age, gender, ethnicity and household address of all residents in Singapore. To be included in this study, participants had to be Singapore residents (Citizens or Permanent Residents) aged between 18–65 years and living in Singapore during the recruitment period. Residents aged 50–65 years, Malays and Indians were over-sampled to ensure sufficient sample size for subgroup analysis. More detailed information on the sampling strategy is found in the paper by Chong et al. .