Systematic review of the clinical and cost effectiveness of ultrasound in screening for developmental dysplasia of the hip in newborns

OBJECTIVE

The objective of this research was to evaluate the effectiveness, clinical impact and costeffectiveness of ultrasound in screening of newborns for developmental dysplasia of the hip (DDH).

METHODS

This systematic review of the evidence on the effectiveness and cost-effectiveness of ultrasound screening of newborns for detecting DDH addressed the following questions:

1. What is the diagnostic accuracy of ultrasound in screening of newborns for DDH?

2. What is the impact of ultrasound in screening of newborns for DDH on the therapeutic decisions and on patient outcomes?

3. What is the cost-effectiveness of ultrasound in screening of newborns for DDH?

4. What is the evidence relating to questions 1,2 and 3 for ultrasound screening of newborns with the method of Graf?

The review was based on the best available clinical and economic studies.

The literature search involved a wide range of medical, economic and grey literature databases. The searches to retrieve literature published from 1975 to March 2004, were not limited by study design, or language. Further studies were identified by examining the reference lists of all included articles. In addition some literature was provided by BSV and by individuals.

Using the inclusion and exclusion criteria two reviewers independently assessed the titles and abstracts for relevance and recorded their decision to order or reject. They then appraised each full manuscript received and made a decision whether to include or exclude each study.

For the evaluation of the diagnostic accuracy of ultrasound in screening for DDH in newborns, all studies that had compared ultrasound, using any method, versus any reference standard (gold standard), and that allowed the generation of 2 x 2 tables, were eligible for inclusion in the review. A reference standard had to be a measure of true disease, i.e. clinically relevant DDH. In addition, all comparative studies of newborns that had evaluated the impact of ultrasound in screening for DDH on the therapeutic decisions and on patient outcomes were included in the review. The comparison could be either with another group using a different screening method or the same population prior to the introduction of the ultrasound screening. For the evaluation of the cost-effectiveness of ultrasound in screening of newborns for DDH, all studies that provided a synthesis of cost and effectiveness data of ultrasound screening for DDH in accordance with the criteria specified for the NHS EED database were eligible for inclusion in the review.

The main outcome measure of effectiveness for studies comparing an ultrasound technique with a reference standard technique for the diagnosis of DDH were to be rates of true disease, true non-disease, false disease and false non-disease (accuracy data).

For studies that had evaluated the impact of ultrasound screening on therapeutic decisions and/or patient outcomes, and for those that had evaluated the method of Graf in the screening of newborns, the outcomes were to include overall treatment rates, rates of operative intervention, rates of abduction splinting, rate of delayed diagnosis, time to treatment, duration of treatment, rate of treatment complications, false diagnostic labelling and any long-term functional outcomes e.g. osteoarthritis.

For economic evaluations, the outcomes reviewed were cost-effectiveness and related assessments.

Specifically the following types of studies were excluded.

• Studies in which the population was a selected one, for example, one that only included infants with clinical signs of DDH or with risk factors for DDH.

• Technical reports describing the technique of ultrasound screening, but containing no clinically relevant outcomes.

In addition, descriptions of clinical experience were excluded from the main analysis. Typically such papers would describe a large screening program with no comparator group, where all cases identified as having ultrasound DDH were treated, where no information was obtained on the natural course of the disease or the incidence of true, clinically relevant DDH.

Data from all included studies were extracted and each study was assessed for quality. The data were combined in a narrative synthesis.

The completed report was posted on the CRD website in September 2002 and comments were invited. The comments received were incorporated into the final version of the report. This did not result in any major changes.