Table 1: Characteristics of studies included in a meta-analysis of the benefit of screening for depression
Study populationOutcomes
StudyDescriptionDefinitionEvaluationDefinitionResults
Oyama et al.19 (5-yr quasi-experimental study in Matsudai, Japan [rural])Total person-years: 11 567 for intervention, 15 055 for control
Age, mean: NR
Age, range: ≥□65 yr
Age, median: NR
Sex, female: 57.6%
Ethnicity: Japanese
Education: NR
Dx: major and minor depression
Older (≥ 65 yr) residents in 6 rural municipalities of southwest and central Japan
Intervention: mental health workshop, referral to general practitioner or follow-up interview with PHN
Exclusions: severely disabled or hospitalized cases were excluded from the study
Screening instrument: SDS
Other rating: RDC
Confirmatory exam: ICD-9
No. of follow-ups: 10
No. of stages: two 10-yr
Main outcome:
Change in risk of completed suicide
Age-adjusted IRRs of completed suicide before and after intervention or control
Main outcome:
Risk of completed suicide in intervention area reduced by 70% among women, no significant change among men
Intervention: IRR 1.02 (95% CI 0.49–2.13) for men and 0.30 (95% CI 0.14–0.67) for women
Control: No significant change
Oyama et al.20 (10-yr quasi-experimental study in Yasuzuka, Japan [rural])Total person- years: 9791 for intervention, 16 032 for control
Age, mean: NR
Age, range: ≥□65 yr
Age, median: NR
Sex, female: NR
Ethnicity: Japanese
Education: NR
Dx: major and minor depression
Older (≥ 65 yr) residents of agricultural rural area in Japan with high suicide rate
Intervention: (a) public health education from 1991 to 2000 and (b) screening for depression with follow-up from 1991 to 1997
Exclusions: NR
Screening instrument: SDS
Other rating: RDC
Confirmatory exam: ICD-9
No. of follow-ups: 7
No. of stages: two 10-yr
Main outcome:
Change in risk of completed suicide
Age-adjusted IRRs of completed suicide before and after intervention or control
Main outcome:
Risk of completed suicide in intervention area reduced by 64% among women, no significant change among men
Intervention: IRR 0.51 (95% CI 0.22–1.19) for men and 0.36 (95% CI 0.14–0.93) for women
Control: No significant change
Oyama et al.17 (10-yr quasi-experimental study in Joboji town, Japan [rural])Total person- years: 9721 for intervention, 17 166 for control
Age, mean: NR
Age, range: ≥□65 yr
Age, median: NR
Sex, female: 50.8%
Ethnicity: Japanese
Education: NR
Dx: depression (unspecified)
Older (≥ 65 yr) residents of agricultural rural area in Japan with high suicide rate
Intervention: 2-step depression screening performed by PHN and psychiatrist with follow-up by psychiatrist every 3 yr in targeted district of intervention municipality, health education and emphasis on suicide taboo every year in 10-yr period from 1990
Exclusions: Older people receiving social welfare
Screening instrument: SDS
Other rating: SADD
Confirmatory exam: ICD-9
No of follow-ups: 10
No. of stages: three 5-yr
Main outcome:
Change in suicide rates
Age-adjusted IRRs of completed suicide before and after intervention or control
Main outcome:
Risk of suicide in intervention area reduced by 73% among men and by 76% among women during implementation decade (relative to pre-implementation decade)
Intervention: IRR 0.27 (95% CI 0.08–0.88) for men and 0.24 (95% CI 0.11–0.52) for women
Control: No significant change
Oyama et al.18 (5-yr quasi-experimental study in Nagawa town, Japan [rural])Total person- years: 1982 for intervention, 16 754 for control
Age, mean: NR
Age, range: ≥□65 yr
Age, median: NR
Sex, female: 59%–60.8%
Ethnicity: Japanese
Education: NR
Dx: depression (unspecified)
Older (≥ 65 yr) residents of agricultural rural area in Japan with high suicide rate
Intervention: 2-step screening for depression and follow-up by PHN, mental health workshop 3 or 4 times a year, group activity program once a month
Exclusions: NR
Screening instrument: SDS
Other rating: RDC
Confirmatory exam: ICD-9
No. of follow-ups: 6
No. of stages: two 6-yr
Main outcome:
Change in risk of completed suicide
Age-adjusted IRRs of completed suicide before and after intervention or control
Main outcome:
Risk of suicide in intervention area reduced by 74% among women, no significant change among men
Intervention: IRR 0.48 (90% CI 0.10–2.31) for men and 0.26 (90% CI 0.07–0.98) for women
Control: No significant change
Oyama et al.21 (5-yr quasi-experimental study in 6 rural municipalities of the Sanpachi Second Medical Zone, Japan [rural])Total person-years: 28 838 for intervention, 27 633 for control
Age, mean: NR
Age, range: ≥□60 yr
Age, median: NR
Sex, female: 57.5%
Ethnicity: Japanese
Education: NR
Dx: depression (unspecified)
Older (≥ 60 yr) residents living in 6 rural municipalities of Sanpachi Second Medical Zone of Japan (mostly agricultural region with high suicide rate)
Intervention: (a) health education and (b) screening for depression with follow-up, using community resources of primary care and public health nursing
Exclusions: NR
Screening instrument: CES-D, DSS, SDS, GDS-5
Other rating: CIDI
Confirmatory exam: ICD-10
No. of follow-ups: 2
No. of stages: two 2-yr
Main outcome:
Change in risk of completed suicide
Age-adjusted IRRs of completed suicide before and after intervention or control
Main outcome:
Risk of suicide in intervention region reduced by 61% among men; no significant change among women
Intervention: IRR 0.39 (90% CI 0.18–0.87) for men and 0.49 (90% CI 0.19–1.22) for women
Control: No significant change

Note: CES-D = Center for Epidemiologic Studies Depression Scale, CI = confidence interval, CIDI = Composite International Diagnostic Interview, DSS = Depression and Suicide Screen, Dx = diagnosis, GDS-5 = 5-item Geriatric Depression Scale,22 ICD = International Statistical Classification of Diseases, IRR = incidence rate ratio, NR = not reported, PHN = public health nurse, RDC = Research Diagnostic Criteria, SADD = schedules of Standardized Assessment of Patient with Depressive Disorders, SDS = Self-rating Depression Scale.23