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. Author manuscript; available in PMC: 2012 Nov 1.
Published in final edited form as: Clin Psychol Rev. 2011 Jul 23;31(7):1169–1182. doi: 10.1016/j.cpr.2011.07.002

Table 5.

Disorganized Schizotypal Symptoms in Relatives of Schizophrenia Probands versus Non-Psychiatric Controls

Study Relatives of Schizophrenia Probands Schizotypy Assessment Comparison with Psychiatrically Healthy Controlsb
Relationship
to Proband (n)		 Sex
% m		 Age
mean yrs		 Psychiatric
Status		 Measure Factor
  Symptom		 screening
criteria (n)		 match to
schiz rels		 effect
size
Kendler et. al, 1995
(Roscommon
Family Study)		 1st degree
relatives (314)		 n/a n/a no schiz
or schizoaff		 SIS Odd Speech Factor
  Cognitive slippage
  Odd speech		 1st degree rels of
unscreened control
probands; no schiz
or schizoaff (575)		 n/a d3 = 0.96**
Kremen et. al, 1998 1st degree
relatives (40)		 22.5% m: 40.8
f: 42.9		 no psychosis
or substance
abuse		 SPQ Disorganized Factor ≤ 70 on the
MMPI-168 (44)		 age, sex,
race		 d5 = 0.22
Yaralian et. al, 2000 relatives (13) 92.3% 29.9 unscreened SPQ Disorganized Factor
  Odd behaviors
  Odd speech		 no family history of
schiz-spectrum
or alcohol/drug
abuse (51)		 age, sex,
race		 d2 = 0.49
  n.s.
  n.s.
Appels et. al, 2004 parents
(36 couples)		 50.0% median:
54.9		 no psychosis
or substance
abuse		 SPQ Disorganized Factor
  Odd Behaviors
  Odd Speech		 no psychotic,
affective, substance,
or personality d/o
(26 couples)		 age, sex,
handedness,
education, IQ		 n.s.
Calkins et. al, 2004 parents, sibs,
offspring (124)		 49.2% 46.5 no psychosis SPQ Disorganized Factor
  Odd Behaviors
  Odd Speech		 no diagnosis (109) sex d1 = 0.17
  d1 = 0.11
  d1 = 0.17
Compton et. al, 2009 parents, sibs,
offspring (28)		 17.9% n/a No psychosis
or mood d/o		 SPQ Cognitive-Perceptual Factor No mood or psychotic
d/o, self or 1st or 2nd
degree rels (32)		 n/a n.s.
Mean Effect Size f or Factor-Level C ompariso ns6 d = 0.73

Note: SIS - Structured Interview for Schizotypy, SPQ - Schizotypal Personality Questionnaire (self-report), MMPI - Minnesota Multiphasic Personality Inventory, unscreened - psychiatric diagnoses not excluded, no diagnosis - all psychiatric diagnoses excluded, schiz - schizophrenia, schizoaff - schizoaffective disorder, SPD - Schizotypal personality disorder, m - male, f – female, rels – relatives, n/a - not reported/not able to calculate, empty cell: not reported by original study, bold font denotes effect size for factor-level comparisons.

a

Torgersen et al, 1993 also reported results for MZ and DZ twins - all comparisons were not significant.

b

Unless otherwise noted, healthy control groups are comprised of individual control probands

1

Glass' d (relative M - control M / control SD)

2

Glass' d calculated by current author

3

Cohen's d (relative M - control M / pooled SD) transformed from odds ratio: d = lno(√3/π) (Hasselblad & Hedges, 1995)

4

Cohen's d transformed from t: d = t(n1+n2)/√df(√n1n2); [pooled, equal variances assumed] (Rosenthal, 1994)

5

Cohen's d transformed from chi square: rφ = √X2/n; d = 2r/√1-r² (Johnson and Eagly, 2000)

6

Mean effect sizes were calculated for factor comparisons using the overall effect size for each study (indicated in bold) by weighting each ‘d’ by the inverse of the conditional variance of ‘d’ (Shadish & Haddock, 1994)

***

p < .001

**

p < .01

*

p < .05

†

p < .10