Included Studies

Location

Observational Period

Participants

Number of

Centers

Timing of Thyroid

Function Testing

Laboratory

Validation

Casey, 2005

USA

Apr. 2000-Apr. 2003

25,765

Single

<20 weeks

FT4, TSH

Casey, 2006

USA

Nov. 2000-Apr. 2003

25,765

Single

<20 weeks

FT4, TSH

Cleary-Goldman,

2008

USA

Oct. 1999-Dec. 2002

10,990

Multiple

1st & 2nd

Trimesters

FT4, TSH

TPO-Ab, TG-Ab

Wikner, 2008

Sweden

Jul. 1995-Dec. 2004

848,468

Multiple

<13 weeks

No

Mannisto, 2009

Finland

Jul. 1985-Jun.1986

9247

Multiple

<20 weeks

FT3, FT4, TSH

TPO-Ab, TG-Ab

Luewan, 2011

Thailand

Jan. 1994-Dec. 2008

540

Single

All trimesters

FT4, TSH

Su, 2011

China

Oct. 2008-Dec. 2010

1017

Multiple

<20 weeks

FT4, TSH

Chen, 2011

Taiwan

Jan.-Dec. 2005

16,980

Multiple

Medical record

No

Wang, 2012

China

2007-2009

756

Multiple

<12 weeks

FT3, FT4, TSH

Mannisto, 2013

USA

2002-2008

223,512

Multiple

Medical record

No

Chen, 2014

China

Feb. 2009-Feb. 2012

8012

Single

All trimesters

FT4, TSH