Table 1

Characteristics of included studies

Study	Design	Setting	Population	Data collection periods	n	Intervention	Comparator	Outcomes measured
Algorithms and guidelines used to manage the admission decision
Armon et al15	Interrupted time series	UK	0–15 years; GP or self- referred	April to July 1997	292 Attendances	An evidence- based guideline for management of children with diarrhoea	Normal practice prior to the implementation of the guideline	Admission rates
								Time taken for treatment
								Re-attendance
				May to August 1999	239 Attendances			Compliance with the guideline
Armon et al15	Interrupted time series	UK		April to July 1997	212 Attendances	An evidence-based guideline for the management of children with seizures	Normal practice prior to the implementation of the guideline	Admission rates
								Time taken for treatment
								Re-attendance
				May to August 1999	199 Attendances			Compliance with the guideline
Perlstein et al16	Historically controlled trial	USA	2 months to 5 yearswith a diagnosis of acute gastroenteritis	December to May 1993/4, 1994/5, 1995/6 and 1996/7	8287 Children	Guideline for the management of acute gastroenteritis	Normal practice prior to the implementation of the guideline	Admission rates
								Compliance with the guideline
								Length of stay
				December to May 1997/8 and 1998/9	3206 Children			Hospital costs
Vazquez17	Historically controlled trial	Spain	0–14 years	January to December 1996	77 Children	Guideline for the management of acute asthma	Normal practice prior to the introduction of the guideline	Admission rates
				January to December 1996	77 Children			Compliance with the guideline
				January to December 1997	68 Children			Readmission rates
Short stay units
Blair et al14	Written questionnaires	UK	Parents of eligible children (no further details provided)	May to July 2003	455	PACU	Accident and emergency depart-ment at night when the PACU was closed	Referral patterns
								Accessibility
								Waiting time
								Self-reported parental anxiety
				A 1-month period	60			Parental expectations
Blair et al 14	Telephone survey, semi-structured interviews, direct observation of patient journeys	UK	Main referrers (GPs), a range of PACU staff	August 2002 to January 2005	70 GPs, 10 PACU staff, 10 patient journeys	PACU	Accident and emergency department	Care processes
								Staff perceptions
								Referrer views
Martinot et al18	Prospective cohort study	France	Infants aged 1–24 months with acute gastroenteritis	1998 and 1999 (no further details)	427 – SSU	Short stay unit in a tertiary centre	Six district general hospitals with no short stay unit	Admission rate
Martinot et al18	Prospective cohort study	France	Infants aged 1–24 months with acute gastroenteritis	1998 and 1999 (no further details)	304 – control	Short stay unit in a tertiary centre	Six district general hospitals with no short stay unit	Length of stay
Gouin et al19	Historically controlled trial	Canada	Children aged 1–18 years presenting with asthma	July 1991 to June 1992	1979 Asthma visits	Paediatric observation unit	Paediatric emergency department	Admission rates
Gouin et al19	Historically controlled trial	Canada	Children aged 1–18 years presenting with asthma	July 1993 to June 1994	2248 Asthma visits	Paediatric observation unit	Paediatric emergency department	Readmission rates
Meates20	Historically controlled trial	UK	Children with respiratory illness, gastroenteritis, febrile convulsions or pyrexia/unwell (no further details)	July to September 1994 and November 1994 to January 1995	1165 Attendances (July–Sept), 1760 attendances (Nov–Jan)	Day assessment ward	Paediatric emergency department prior to the opening of the day assessment unit	Admission rates
Meates20	Historically controlled trial	UK		July to September 1995 and November 1995 to January 1996	1725 Attendances (July–Sept), 1840 attendances (Nov–Jan)	Day assessment ward

GP, general practitioner; PACU, paediatric ambulatory care unit; SSU, short stay unit