Table 1 Details on studies used in the analyses

Brief description

Study of PMH in the general population sample

Assessment of level of PMH in patients with psychiatric conditions

Assessment of level of PMH in informal caregivers of older adults

Representative general population survey of health and lifestyle behaviours

Study period

Dec 2010 - Feb 2011

Jan 2014 - Jun 2015

Jan 2015 - Apr 2016

Apr 2014 - Mar 2015

Ethical aspects

Study was approved by the Institutional Ethics Committee. Return of questionnaires was considered as implied consent.

Study was approved by the Institutional Ethics Committee. Written informed consent was obtained from all participants

Study was approved by the Institutional Ethics Committee. Written informed consent was obtained from all participants.

Study was approved by the Institutional Ethics Committee. Written informed consent was obtained from all participants and legal representatives of those aged < 21 y

Study sample

Singapore residents aged 21–65 years of Chinese, Malay or Indian ethnicity

Singapore residents aged 21–65 years of Chinese, Malay or Indian ethnicity

Singapore residents aged 21–65 years of Chinese, Malay or Indian ethnicity

Singapore residents aged 18–79 years of all ethnic groups

Sampling

Convenience, quota sampling through household visits and street intercepts

Convenience sampling through referrals from clinicians

Convenience sampling of caregivers of community-based older adults and older mental health service users

Representative general population sample, probability sampling

Data/ Measures

Sociodemographic information (age, gender, ethnicity, marital status, education level)

PMHI (47 items)

EQ-5D-5 L, K6 distress scale

Analyses conducted in the current study

Confirmatory factor analysis

Internal consistency reliability

Agreement with original measure (intraclass correlation coefficient)

Concurrent validity

Floor and ceiling effect

R-PMHI score estimates and socio-demographic correlates