- John A James, general practitionera,
- Gabrielle J Laing, consultant in community paediatricsb,
- Stuart Logan, senior lecturer in paediatric epidemiologyc,
- Michael Rossdale, general practitionerd
- a Montpelier Health Centre, Bristol BS6 5PT
- b Department of Child Health, St Leonard's, London N1 5LZ
- c Department of Epidemiology and Biostatistics, Institute of Child Health, London WC1N 1EH
- d 111 Pembroke Road, Bristol BS8 3EU
- Correspondence to: Dr James
- Accepted 16 January 1997
Iron deficiency is the commonest cause of anaemia in children in the United Kingdom and is reported to be associated with psychomotor delay; it is reversible by iron treatment.1 2 Screening for iron deficiency anaemia in toddlers could become a routine part of child health promotion.3
Screening at 13-14 months was introduced in an inner city practice (by JAJ) in 1987. Coverage exceeds 90%.4 We examined the feasibility of extending screening to other practices in the same city. Practices 1 (JAJ) and 3 serve deprived inner city communities with half of the population from ethnic minority groups; practice 2 serves a relatively affluent population; practices 4 and 5 have largely working class populations.
Subjects, methods, and results
The screening programme was agreed between JAJ and general practitioners from four other practices who expressed an interest in the programme. Screening for iron deficiency anaemia (haemoglobin concentration <110 g/l, based on estimation by a single laboratory) was offered to all children attending for routine measles, mumps, and rubella immunisation. All practice nurses were trained in thumb prick capillary blood sampling, and a sample was taken from children whose parents gave consent.
Numbers of children offered screening, parents refusing, samples on which estimations could not be performed (sample insufficient or clotted), and anaemic children were recorded for each practice. Screening continued for up to 24 months; practice 3 abandoned the project at six months because of time constraints, parental objections, and technical difficulties in obtaining blood samples.
Population coverage for each practice was estimated by multiplying the proportion of children offered the screen in whom a haemoglobin concentration was obtained by the immunisation coverage for that practice. Up to 32% of parents refused screening, and the a haemoglobin concentration was obtained in 39-100% of those offered screening. The estimated prevalence of anaemia was 23% overall (range 0-35%) (table 1).
Forty nine parents (11%) declined screening. Half felt the test was not necessary; others considered the test traumatic, and one quarter said they would “think about the test” and come back. None did.
Iron deficiency anaemia is common in toddlers, even in the more affluent population of practice 3 (prevalence 15.3%). The screening programme was successful in only one of the four new practices. Two practices achieved reasonable proportions of haemoglobin estimations, although in one with low uptake of immunisation the estimated population coverage rate was only around 70%. In the fourth practice, high rates of parental refusal and failure to obtain analysable samples led to abandonment of the programme after six months.
All four practices provide child health promotion for their patients and entered the study as eager volunteers. A successful screening programme must have high coverage; the population not screened generally has higher rates of abnormality. Although enthusiasts have reported successful screening programmes for iron deficiency anaemia in primary care, relatively poor coverage was achieved in three practices in spite of their commitment (practices 1, 2, and 3 together obtained haemoglobin concentrations in 77% of children offered screening, an estimated population coverage of 63%). An attempt to introduce screening for iron deficiency anaemia into community clinics in a deprived London district was even less successful, with an uptake of under 10% in nearly 600 children invited for screening (GJ Laing, unpublished data).
Success would require that health professionals and parents were convinced of the benefits of detecting and treating iron deficiency anaemia; that staff were well trained and experienced; that adequate time was available; and that high uptake of measles, mumps, and rubella vaccine was maintained. The difficulties identified, in combination with the fluctuating nature of iron deficiency in this age group,5 suggest that population screening for iron deficiency anaemia is unlikely to be an appropriate strategy. Population based interventions may prove more effective.
Funding: South West Research and Development NHS Funding.
Conflict of interest: None.