Apr 2, 2008
Asthma in young children: clinical practice guidelines do not provide a reference standard for diagnosis
IQWiG completes partial commission for the preparation of new DMPs
No reference standard for asthma diagnosis in children between 2 and 5 years can be inferred from current clinical practice guidelines (CPGs) of high methodological quality. This is the result of a final report by the Institute of Quality and Efficiency in Health Care (IQWiG) published on 2 April 2008.
In July 2006, the German Federal Joint Committee (G-BA) commissioned IQWIG to assess which diagnostic procedures were best suited to diagnose asthma in preschool children. In addition, the Institute was to assess which benefits and harms could arise in these children from the therapeutic interventions following an asthma diagnosis. On the basis of the IQWiG expertise, the G-BA seeks an answer to the question as to whether, and, if so, how disease management programmes (DMPs) for preschool children should be implemented. So far, only children over the age of 5 can be registered in the asthma DMP.
Diagnosis in young children is particularly difficult
The reliability of diagnosis is of particular relevance in this patient group. Asthma often starts in early childhood, but is often difficult to diagnose in this age group. For technical reasons, some diagnostic procedures cannot be used in children under 5, and school children often no longer show typical asthma symptoms. On the one hand, no cases of asthma should be overlooked, so that appropriate therapy can be initiated at an early stage. On the other hand, children who are not in fact suffering from chronic asthma should not receive unnecessary treatment that could cause potential harm.
Clinical practice guidelines do not present an algorithm for individual diagnostic steps
In its first partial commission (V06-02A), IQWiG therefore investigated the question as to which diagnostic procedures were recommended for suspected asthma in young children, and whether a reference standard existed against which the diagnostic reliability of individual procedures could be measured. In this context, a systematic search was performed to identify published CPGs. These CPGs were then assessed with regard to whether a reference standard was described or could be inferred from the recommendations provided.
The result was clear: no diagnostic procedure was specifically described as a reference standard in any of the 14 CPGs included in the analysis by IQWiG. It was stressed in all asthma CPGs that a diagnosis should be made through the combination of different diagnostic steps. However, no specific algorithm could be inferred from the CPGs, i.e. which steps should be combined in which sequence (particularly concerning 2- to 5-year olds). For this age group, symptoms were linked to specific risk factors in only two CPGs.
Procedure of report preparation
IQWiG published the preliminary report on its website on 17 September 2007. Comments on this version could be submitted until 15 October. Three comments were received, which, however, did not contradict the general conclusion of the preliminary report; nor were additional relevant publications not identified by IQWiG cited in the comments. As the comments posed no questions needing discussion, IQWiG dispensed with an oral scientific debate. However, the comments were taken into account; the objections raised are discussed in the final report (pp. 75-78) and are presented in their entirety in a separate document. On 6 February 2008 the final report was sent to the contracting agency, the G-BA.
Report plans, but so far no preliminary reports, have been published on the other partial commissions V06-02B (Evaluation of drug and non-drug interventions in children with bronchial asthma aged from 2 to 5 years) and V06-02C (Evaluation of different investigational methods used in diagnosing bronchial asthma in children aged from 2 to 5 years). One partial commission is built upon the other; the evaluation of current recommendations on diagnostic procedures (V06-02A) serves as a basis for the subsequent evaluation of diagnostic procedures (V06-02C).
Contact: Tel. +49(0)221-35685-0, info@iqwig.de