Evaluation of the cost/effectiveness ratio of systematic antenatal screening for malformations.
There is a need to quantify precisely the long term outcome of fetal malformations and the required amount of medical care and social assistance. The practice of ultrasound examination for the routine survey of the pregnancies benefits the detection of fetal age assessment, growth anomalies and malformations. A large gap still remains between the theoretical possibility of the detection of malformations by ultrasound and the results of routine surveys. The specialized centres performing ultrasound on risk patients tend nowadays to spread its application to all the pregnancies they follow. However, cost effectiveness ratio of such a practice has never been evaluated. The evaluation might bring arguments to 'decide' whether this kind of screening should or should not be generalized to all pregnant women.
'Cost effectiveness analysis' (CEA) identifies programs that are technically efficient. 'Cost utility analysis' (CUA) is a variant of CEA; the benefits are measured in terms of quality adjusted life years (QUALYS) gained. 'Cost benefit analysis' (CBA) identifies programs that are allocatively efficient. The study is a mixture of CEA, CUA and CBA and examines how the health service can increase benefits for fixed resources, whether it would be beneficial to devote more resources to antenatal health care, and what the implications might be for the quality of life of the fetus and the parents.
The quality of diagnosis is strongly influenced by the:
kind of malformation;
optimal date of the examination;
ability level of operator;
contents of examination and time spend for screening.
The study is designed to help to delineate the realistic field of possible detectable anomalies (compared to the case report level).
The effectiveness depends on:
- the accuracy of the diagnosis
- its capacity to reduce the frequency of handicaps.
The cost-price of the screening includes
- the ultrasound examinations,
- the complementary investigations,
- hospital and treatment expenses, because of antenatal diagnosis of malformation (true or not) reduced with the costs of handicap when no screening is performed.
Effectiveness and costs first depend on the considered type of malformation requiring a large number of cases and justifying a broad multicentric study. The programme includes:
1. The Sensitivity & Specificity
The Sensitivity & Specificity of screening for malformations, the record of examinations and treatments following screening.
Ante & postnatal diagnosis of malformations, and birth data from the records of the participating centres.
For malformations whose prevalence is 0.05%, a sample of 200.000 pregnancies is needed.
As specificity is measured in a sample of newborns without defects, such a sample size would allow to estimate it with a confidence interval smaller than 0.01%.
2. An economic study
1) The cost of ultrasound screening, and of subsequent procedures (examinations, hospitalizations, treatments),
2) The medical cost, and cost of social charge for handicapped children born without having a screening.
2.A. Technical efficiency:
1) when the maximum benefits are produced for a fixed cost, or, conversely,
2) when a fixed benefit is achieved at minimum cost.
'Cost-effectiveness analysis' (CEA) aims to identify programs that are technically efficient. 'Cost-utility analysis' (CUA) is a variant of CEA; the benefits are measured in terms of quality-adjusted life-years (QUALYS) gained.
2.B. Allocative efficiency:
when resources are allocated so as to gain the maximum excess of benefit over cost (where neither the benefit nor the cost is fixed in advance).
'Cost-benefit analysis' (CBA) aims to identify programs that are allocatively efficient.
The study is a mixture of CEA, CUA and CBA and will examine how the health service can increase benefits for fixed resources, whether it would be beneficial to devote more resources to antenatal health care, and what the implications might be for the quality of life of the fetus and the parents.
3. A psychological evaluation
Evaluation of psychological consequences of screening and its influence on cost-benefit.