Table 1.

A summary of the studies included detailing country of origin, study type, data source, total number of infants studied, number of infants within study group who were exposed to erythromycin, and subsequently developed IHPS and the weight of the study in the meta-analysis

Study (year)	Country	Study type	Source of data	Total number of infants	Number of infants exposed to erythromycin who developed IHPS	Study weight (%)
Ng et al. (2001) [10]	China	Randomised control trial	Preterm infants admitted to the neonatal unit at Prince of Wales Hospital, Hong Kong from November 1998–May 2000	29	0	/
Cooper et al. (2002) [11]	United States	Cohort study	Medicaid or TennCare (Tennessee’s program for Medicaid enrollees and uninsured individuals) births in Tennessee from 1985–1997	306891	9	18
Eberly et al. (2015) [12]	United States	Cohort study	Infants born between 1 June 2001 and 1 April 2012 registered with the TRICARE Management Activity military health system (MHS) database	1069900	17	19.2
Mahon et al. (2001) [13]	United States	Cohort study	Infants born from 1 June 1993–31 December 1999, Wishard Hospital, Indianapolis	14407	4	15
Honein et al. (1999) [14]	United States	Cohort study	Infants born in a community hospital from January–February 1999	125	7	5.3
Ludvigsson et al. (2016) [9]	Sweden	Cohort study	Nationwide cohort of infants born between July 2005 and December 2010	582256	0	5.5
Ericson et al. (2015) [15]	United States	Cohort study	Infants from 348 NICUs managed by the Pediatrix Medical Group between 1997–2012	19001	10	17.9
Lund et al. (2014) [16]	Denmark	Cohort study	All liveborn singleton infants in Denmark between 1 January 1996 and 31 December 2011	999378	16	19.1
Mohammadizadeh et al. (2010) [17]	Iran	Randomised control trial	Uncomplicated preterm infants (28–34 weeks) born in Shahid-Beheshti and Al-Zahra Hospitals affiliated with the Isfahan University of Medical Sciences	35	0	/