Supplemental Digital Content 3 Materials and methods of studies included in the meta-analysis
Geulayov et al. 2015 [15]
Participants were drawn from a target population of men who belonged to a population based longitudinal study: The Israel Study of Glucose Intolerance, Obesity, and Hypertension (The Israel GOH Study). Of 2,800 men born in 1922–1941, randomly sampled from the Israel Population Registry according to age and ethnic origin distribution 2,000 (71%) were recruited for Phase-1 of the study and 1,200 (63%) of them survived and consented to participate in Phase-2. They were the target population for the present study, where 797 men were randomly sampled for an interview on SOC in 1989.
Haukkala et al. 2013 [22]
The participants of this study were from psychosocial subsamples of two national cardiovascular risk factor surveys (the National FINRISK Study) that were conducted in Finland in 1992 and 1997 (19). In 1992, the study population for the baseline survey comprised 25- to 64-year-old Finnish men and women from four areas of Finland. In 1997, the participants in the baseline study were 25- to 74-year-old men and women from the same four areas and, in addition, one northern province. In 1992 and 1997, a random sample of people between 25 and 64 years old was drawn from the Finnish population register so that each area (10-year age group and both sexes) included 250 participants. In addition, a random sample of 500 men and 250 women between 65 and 74 years old was taken from two areas in 1997. The total sample size was 8000 in 1992 and 11,500 in 1997.
First, one third of the sample were randomly selected for a food diary sub-study, and the remaining two thirds of the sample were selected for this study of psychosocial factors in 1992 (n = 5105) and 1997 (n = 7103).
KIHD [13] SOC data introduced in this publication
KIHD consists of a random sample of 3433 eligible men, who were living in the city of Kuopio or surrounding areas in 1984. Of these 3433 men, 553 refused and 198 were excluded due to death, serious illness, or migration away from the study area. Consequently, 2682 men participated.
Mattisson et al. 2014 [17]
The Lundby Study is an epidemiological study that started in 1947. The population was geographically defined and comprised two parishes in south Sweden, which were rural in the 1940s but have since undergone considerable changes. The original 1947 cohort consisted of 2550 subjects. In 1957, 1013 subjects were added that either had been born into the area or had moved there; no additional subjects have been added since then. In 1997, 1559 out of 1779 (87.6%) participants in the cohort were interviewed and 1164 (65.4%) completed the SOC questionnaire.
Nilsen et al. 2016 [18]
Study sample comes from the 1991 Swedish Level of Living Survey (LNU). LNU 1991 is a nationally representative study based on a random sample of all people in Sweden aged 18–75 years. Data were collected in face-to-face interviews, and the response rate was 79.1%.
Poppius et al. 2003 [26]
The participants were men aged 40–55 at recruitment in 1981–1982 for the Helsinki Heart Study (HHS), a 5-year randomized, double blind, placebo-controlled primary prevention trial of gemfibrozil, a lipid-lowering drug. The participants were selected via two successive screenings among employees at two state agencies and five industrial companies. Postal invitations were sent to 23,531 men and 18,966 at- tended the first screening (80.6%). The psychosocial questionnaire
was distributed first to the trial groups in 1986 with a participation rate of 79%. Later in 1987–1988 the control groups also completed the questionnaire (participation rate 65%).
Super et al. 2014 [16]
The sampling frame for the prospective cohort study was the study population of the Monitoring Project on Chronic Risk Factors (MORGEN project). Data were collected on health status and risk factors from a random sample of 20–65-year-old inhabitants of three cities in the Netherlands (Amsterdam, Doetinchem and Maastricht) from 1993 to 1997. In total, 23 100 participants completed a general questionnaire on risk factors and health and a food frequency questionnaire.
Participants, who gave consent for further research (94%), were invited to complete the Health and Lifestyle Questionnaire (HLEQ) designed to study the relationship between psychosocial factors and disease.
Wainwright et al. 2008 [21]
During 1993–1997, 30,414 men and women (then) aged 40–74 years and residing in Norfolk, United Kingdom, were recruited for the European Prospective Investigation into Cancer (EPIC)- Norfolk population study by using general practice age-sex registers. During 1996–2000, a total of 20 921 (of 28 582 eligible EPIC-Norfolk) participants completed the Health and Life Experiences Questionnaire (HLEQ) that included a three-item SOC scale.
