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Table 1 Diagnostic statistics of imputed suicidal ideation among Millennium Cohort Study participants at 2007 survey, n = 63,028

From: Multiple imputation validation study: addressing unmeasured survey data in a longitudinal design

  Self-reported RAN PHQ-BIN PHQ-ORD ALL-BIN ALL-ORD
True negative 60,475 58,032
(57,873–58,192)
58,965
(58,815–59,114)
58,103
(57,955–58,251)
59,001
(58,844–59,157)
58,137
(57,985–58,288)
True positive 2553 104 (73–134) 861 (778–944) 1611 (1530–1693) 967 (885–1049) 1689 (1606–1772)
False negative 2450 (2352–2548) 1692 (1592–1792) 942 (877–1006) 1587 (1492–1682) 865 (803–927)
False positive 2442 (2313–2571) 1510 (1394–1626) 2372 (2257–2487) 1473 (1348–1598) 2338 (2218–2457)
Prevalence 4.05 4.04 (3.79–4.29) 3.77 (3.44–4.08) 6.32 (6.01–6.64) 3.87 (3.55–4.20) 6.39 (6.07–6.71)
Sensitivity 4 (3–5) 34 (31–37) 63 (61–65) 38 (35–41) 66 (64–68)
Specificity 96 (96–96) 98 (97–98) 96 (96–96) 98 (97–98) 96 (96–96)
PPV 4 (3–5) 36 (34–39) 40 (39–42) 40 (37–42) 42 (40–44)
NPV 96 (96–96) 97 (97–97) 98 (98–99) 97 (97–98) 99 (98–99)
CPU time 2:32:48.60 2:26:04.96 70:55:18.03 71:09:58.09
  1. CPU: central processing unit; reported in hours, minutes, seconds; NPV: negative predictive value; PCL-C, PTSD Checklist−Civilian Version; PHQ, Patient Health Questionnaire; PPV: positive predictive value; PTSD, posttraumatic stress disorder
  2. Self-reported suicidal ideation was indicated if reported “several days” or more to “thoughts that you would be better off dead or hurting yourself in some way”
  3. RAN: suicidal ideation was randomly assigned in line with the prevalence observed in the sample in 2007
  4. PHQ-BIN model: treated suicidal ideation as a dichotomous variable and included the remaining 8 PHQ items in the imputation model
  5. PHQ-ORD model: treated suicidal ideation as a 4-level variable and included the remaining 8 PHQ items in the imputation model
  6. ALL-BIN model: treated suicidal ideation as a dichotomous variable and included the 8 PHQ items and previously identified factors from the literature: sex, age, race/ethnicity, marital status, education attainment, 10 individual items from the RAND physical functioning module, 17 individual items and PTSD screener from the PCL-C, smoking status, sleep duration, and 5 alcohol use items from the PHQ [27,28,29,30]
  7. ALL-ORD model: treated suicidal ideation as a 4-level variable and included the 8 PHQ items and previously identified factors from the literature: sex, age, race/ethnicity, marital status, education attainment, 10 individual items from the RAND physical functioning module, 17 individual items and PTSD screener from the PCL-C, smoking status, sleep duration, and 5 alcohol use items from the PHQ [27,28,29,30]