In this issue we look at a recent trial of school dental screening in the UK. This has been a feature of UK children's dental services for over 100 years. Recently it has been endorsed by the World Health Organization, which stated that, “Screening of teeth and mouth enables early detection and timely interventions towards oral diseases and conditions, leading to substantial cost savings. It plays an important role in the planning and provision of school oral health services as well as health services”. The trial discussed in this issue found that school dental screening delivered according to three different models was not effective at reducing levels of active caries and increasing attendance at dental practices in the population under study. It was a large, well-designed study: should we therefore, on the basis of this evidence, stop the programme? I would suggest that, at the present time, the answer to this is no.

Screening is defined by the UK National Screening Committee (NSC) as, “a public health service in which members of a defined population, who do not necessarily perceive they are at risk of, or are already affected by a disease or its complications, are asked a question or offered a test, to identify those individuals who are more likely to be helped than harmed by further tests or treatment to reduce the risk of a disease or its complications” (see www.nsc.nhs.uk/whatscreening/whatscreen_ind.htm). Screening is often seen as a single test and for many years the criteria for appraising screening were based on the Wilson and Jungner criteria1 (Figure 1, below left).

Figure 1
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The Wilson-Jungner1 criteria for appraising the validity of a screening programme

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There is constant pressure to introduce screening tests for a wide range of conditions. In order to cope with this the UK National Health Service was instructed not to introduce any new screening programmes until the NSC had reviewed their effectiveness. With the establishment of the NSC there was a change in focus from specific screening tests to the development of effective screening programmes because, for screening to be effective, all the steps from identification of the population at risk, to diagnosis of the disease or precursor, to treatment of the individual, must be effective. To achieve this, the NSC assesses proposed new screening programmes against a set of internationally recognised criteria2 covering the condition, the test, the treatment options and effectiveness and acceptability of the screening programme (Figure 2, next page).

Figure 2
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UK National Screening Committee. Criteria for appraising the viability, effectiveness and appropriateness of a screening programme (see www.library.nhs.uk/screening)

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Assessing programmes in this way is intended to ensure that they do more good than harm at a reasonable cost. Currently the NSC is reviewing screening of dental disease, as noted by our commentator on page 5. Their interim report highlights three areas that need to be addressed:

  • Could attendance resulting from screening be improved?

  • Could treatment rates following referral be improved?

  • What means might be used to maintain surveillance of dental health of children if the programme were to be abandoned?

I believe that we need greater clarity on these issues before we abandon school dental screening here in the UK.