Table 1

Details of studies with a comparison group

First author	Population	Definition of FTT	Duration of follow up	Adequacy of follow up	Controls	Blinding at assessment	Potential confounders reported in the study
Population based studies
Mitchell, 1980¹²	19 of 30 children with history of FTT prior to 24 months of age in a primary care clinic of 312 identified by review of notes	<80% normal wt, or FTT cited on the problem list	At 3–6 years	12 of 19 cases 16 of 19 controls	Controls matched at inception for age, maternal age, marital status, and family problems	Blinded for McCarthy Scale and behavioural questionnaire but not growth	Life events score, sex, mother’s education, FTT

Corbett, 1996¹³	52 children identified as FTT by child health surveillance from 306 eligible children registered in 2 clinics	A fall of 2 centile lines for weight, sustained for >1 month	5 years later	48 of 52 (89%) cases and 46 of 52 (88%) controls	Next child on clinic register of same age and sex	Psychologists blind to child’s status	No control for confounders

Drewett, 1999¹⁴	136 children with FTT identified from a birth cohort of 3418	Thrive index <5% on 2 or more occasions between ages 3–18 mth	At 7–9 years	IQ testing: 79% cases, 87% controls   >Growth measures: 82% cases, 91% controls	Selected from cohort for normal growth and matched for age and residential area	Psychologists blind to child’s status	Maternal IQ, parental height, organic disease, maternal smoking, breast feeding, family size, birth order

Kerr, 2000¹⁵	92 children with FTT, of 193 children enrolled in a longitudinal study of child development and maltreatment	Weight <5th centile Age <25 mth   >Normal birth wt	At 6 y of age	Not clear	101 children with wt >10% matched for age, race, sex, and SES	No detail given	Maltreatment as defined by a Child Protective Services Report for neglect, sexual or physical abuse, SES, age, gender

Boddy, 2000¹⁶	47 children identified as FTT by the age of 12 months from a cohort of 2004 births in 1986 and still resident in the area	Weight at 12 mth at or <3rd centile and sustained for at least 3 mth	At 6 years	IQ testing: 42 of 47 cases, 42 of 47 controls   >Growth measures: 38 cases, 39 controls	Matched at inception for birth wt, sex, ethnicity, and residential area	Blinded for growth, unclear if blinded for IQ testing	Maternal height, maternal IQ, changes in social index

Clinical sample based studies
Singer, 1984¹⁷	13 babies hospitalised at age 5–9 months for FTT	Weight <3%	At 3 years	All 13 cases, 9 of 13 organic FTT and 5 of 13 controls	Selected at inception from children attending the emergency room, but no details given. At F/U the remaining controls had higher BW, gestational age and parental education	No details given	Parental education

Drotar, 1992¹⁸	68 hospitalised infants aged 1–9 months, randomly assigned to 3 types of intervention	Normal birth weight decreasing to weight <5th centile Weight gain demonstrated in hospital	Age 42–48 mth	48 of 68	47 controls matched at inception for age, sex, ethnicity, social factors, mother’s education	No comment on blinding of assessors	Effect of treatment group

Reif, 1995¹⁹	86 children diagnosed with FTT at <2 years of age either as in or outpatients	Age <2 y, weight, height <5th centile for at least 6 mth, term infants	5 years later	61 of 86 children	65 controls matched at assessment for age, sex, social setting, ethnicity (but birth wt and maternal ht were higher)	No comment on blinding of assessors	Birth weight, severity of growth delay, parental heights, parental education