. Author manuscript; available in PMC: 2016 Jan 31.

Published in final edited form as: JAMA Psychiatry. 2015 Feb 1;72(2):169–178. doi: 10.1001/jamapsychiatry.2014.2406

Table 1.

Demographic and Clinical Characteristics of the Attempter and Nonattempter MDD Groups^a

Characteristic

Study Group

Group Comparison

Suicide Nonattempters (n = 62)

Suicide Attempters (n = 29)

Test Statistic

P Value

Age, y

40.4 (12.4)

34.6 (12.3)

t₈₉ = 2.11

.04

Educational level, y

14.9 (3.2)

14.1 (4.3)

t₈₉ = 1.03

.31

HDRS-24 score

25.7 (6.7)

27.6 (6.1)

t₈₉ = −1.29

.20

Beck Depression Inventory score

26.8 (9.6)

30.7 (10.4)

t₈₇ = −1.73

.09

Beck SSI score

3.4 (5.5)

9.7 (11.6)

t₈₉ = −3.52

.001

Beck Suicide Intent Scale score

14.4 (5.0)

Lethality of attempt score

1.6 (1.7)

Lifetime aggression score^b

18.2 (4.9)

19.2 (5.1)

t₇₅ = −0.83

.41

Global Assessment Scale score

54.0 (10.6)

48.0 (10.9)

t₈₉ = 2.52

.01

Reasons for Living Scale score

2.2 (2.4)

1.6 (1.9)

t₈₉ = 1.03

.30

Beck Hopelessness Scale score

9.9 (6.7)

13.3 (5.3)

t₈₉ = −2.39

.02

Age at onset of MDE, y

23.5 (12.1)

17.9 (10.3)

t₈₉ = 2.17

.03

Female sex, %

64.5

65.5

χ_{1}^{2} = 0.009

.93

Cluster B personality disorder, %

12.2

32.0

Fisher exact test

.06

Lifetime history of abuse, %

56.7

60.7

χ_{1}^{2} = 0.128

.72

History of abuse before 15 years of age, %

45.0

46.4

χ_{1}^{2} = 0.016

.90

SSI score >0 at baseline, %^c

37.1

48.3

χ_{1}^{2} = 1.023

.31

Specific activity, mCi/nmol

3.85 (1.80)

3.55 (1.85)

t₈₉ = 0.72

.47

Injected dose, mCi/kg

0.09 (0.05)

0.10 (0.04)

t₈₉ = −0.96

.34

Injected mass, mg/kg

0.02 (0.01)

0.03 (0.02)

t₈₉ = −1.69

.09

f_P, %

6.44 (2.26)

6.21 (2.13)

t₈₉ = 0.45

.65

V_T(CWM), mL/cm³

0.29 (0.09)

0.27 (0.10)

t₈₉ = 0.89

.38

Abbreviations: f_P, plasma-free fraction; HDRS-24, 24-item version of Hamilton Depression Rating Scale; MDD, major depressive disorder; MDE, major depressive episode; NA, not applicable; SSI, Scale for Suicide Ideation; V_T(CWM), volume of distribution in cerebellar white matter.

SI conversion factor: To convert millicuries to millibecquerels, multiply by 3.7 × 10¹⁰.

Unless otherwise indicated, data are expressed as mean (SD).

Determined using the Brown-Goodwin Lifetime History of Aggression Scale for 51 nonattempters and 26 attempters.

Indicates some ideation is present at entry into the study.