. Author manuscript; available in PMC: 2019 Nov 1.

Published in final edited form as: Paediatr Perinat Epidemiol. 2018 Oct 18;32(6):512–532. doi: 10.1111/ppe.12505

Table 2.

Newcastle-Ottawa scale assessment of the eligible studies.

# (by study/year of publication)	Star cate-go-ries	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21
Study or location		Jamaica	OPPS^a								MHPCD^a						NMIHS	OH^a		NJ/PA^a		IDEAL
Author, year		Hayes, 1991	Fried, 1988	Fried, 1990	Fried, 1992	Fried, 1992	O’Connell, 1991	Fried, 1997	Fried, 1998	Fried, 2000	Day, 1994	Leech, 1999	Goldschmidt, 2008	Goldschmidt, 2000	Richardson, 2001	Goldschmidt, 2004	Faden, 2000	Noland, 2003	Noland, 2005	Bennett, 2008	Carmody, 2011	Chakraborty, 2015
1) Representativeness of the exposed cohort
a) Truly representative of the average demographics in the community	^*																^*
b) Somewhat representative of the average demographics in the community	^*	^* (Rural lower income community)									^* (Lower income population)							^* (Lower income)				^* (Lower income and educa-tion)
c) Selected group of users, e.g. nurses, volunteers			Volunteers responding to advertisement of the study, low-risk sample																	Volun-teers
d) No description of the derivation of the cohort
2) Selection of the non-exposed cohort
a) Drawn from the same community as the exposed cohort	^*	^*	^*								^*						^*	^*		^*		^*
b) Drawn from a different source
c) No description of the derivation of the non-exposed cohort
3) Ascertainment of exposure
a) Secure record (e.g. surgical records)	^*	^*^b																^*		^*		^*
b) Structured interview	^*		^*								^*						^*
c) Written self-report
d) No description
4) Demonstration that outcome of interest was not present at start of study^c
a) Yes	^*	^*	^*								^*						^*	^*		^*		^*
b) No
Comparability
1) Comparability of cohorts on the basis of the design or analysis
a) Study controls for _exposure to tobacco_	^*	^*	^*								^*						^*	^*		^*		^*
b) Study controls for any additional factor	^*	^*	^*								^*						^*	^*		^*		^*
Outcome
1) Assessment of outcome
a) Independent blind assessment	^*	^*	^*								^*						^*	^*		^*		^*
b) Record linkage	^*
c) Self-report
d) No description
2) Was follow-up long enough for outcomes to occur?
a) Yes	^*	^* (5y)	^* (1–2y)	^* (3–4y)	^* (5–6y)	^* (6y)	^* (6–9y)	^* (9–12y)	^* (9–12y)	^* (9–12y)	^* (3y)	^* (6y)	^* (6y)	^* (10y)	^* (10y)	^* (10y)	^* (3y)	^* (4y)	^* (4y)	^* (4–9y)	^* (6–11y)	8 (4.5y)
b) No
3) Adequacy of follow up of cohorts
a) Complete follow up – all subjects accounted for	^*						^*
b) Subjects lost to follow up unlikely to introduce bias – small number lost - > 80% follow up, or description provided of those lost	^*	^*(92%)									^* (88%)	^* (80%)	^* (85%)	^* (83%)	^* (83%)	^* (83%)	^* (83%)		^* (80%)	^* (80%)		^* (97%)
c) Follow up rate < 80% and no description of those lost			71%	70%	73%	67%		77%	77%	77%								76%			65%
d) No statement
Total score:		8.5	7	7	7	7	8	7	7	7	9	9	9	9	9	9	9	8	9	8	7	7

^*-

Article has met requirement to be awarded a star (1 score point)

^0–

Article’s standing in an assessment category, when no star is awarded

^a–

When all articles belonging to a single study received same score, the cells were combined to save space.

^b–

Study has met the requirement to be awarded the star, however, this information was not in the reviewed article, and was found in a different publication that did not meet eligibility criteria for this review (.5 score point)

^c–

As outcome of interest is affected cognitive development, all articles were awarded star for this question since all studies had enrolled participants at birth.

OPPS – Ottawa Prenatal Prospective Study, Canada

MHPCD – Maternal Health Practices and Child Development Project, Pennsylvania, USA

NMIHS – National Maternal and Infant Health Survey, USA

OH – Prenatal cocaine exposure study, Ohio, USA

NJ/PA – Developmental effects of prenatal substance exposure study, New Jersey/Pennsylvania, USA

IDEAL - Infant Development, Environment, and Lifestyle study, New Zealand