Development of a fragile X syndrome (FXS) knowledge scale: towards a modified multidimensional measure of informed choice for FXS population carrier screening.
BACKGROUND
Genetic carrier screening is increasingly possible for many conditions, but it is important to ensure decisions are informed. The multidimensional measure of informed choice (MMIC) is a quantitative instrument developed to evaluate informed choice in prenatal screening for Down syndrome, measuring knowledge, attitudes and uptake. To apply the MMIC in other screening settings, the knowledge scale must be modified.


OBJECTIVE
To develop and validate a modified MMIC knowledge scale for use with women undergoing carrier screening for fragile X syndrome (FXS).


METHODS
Responses to MMIC items were collected through questionnaires as part of a FXS carrier screening pilot study in a preconception setting in Melbourne, Australia.


METHODS
Ten knowledge scale items were developed using a modified Delphi technique. Cronbach's alpha and factor analysis were used to validate the new FXS knowledge scale. We summarized the knowledge, attitudes and informed choice status based on the modified MMIC.


RESULTS
Two hundred and eighty-five women were recruited, 241 eligible questionnaires were complete for analysis. The FXS knowledge scale items measured one salient construct and were internally consistent (alpha = 0.70). 71% (172/241) of participants were classified as having good knowledge, 70% (169/241) had positive attitudes and 27% (65/241) made an informed choice to accept or decline screening.


CONCLUSIONS
We present the development of a knowledge scale as part of a MMIC to evaluate informed choice in population carrier screening for FXS. This can be used as a template by other researchers to develop knowledge scales for other conditions for use in the MMIC.
Department of Paediatrics, The University of Melbourne, Parkville, Vic., Australia; Genetics Education and Health Research, Murdoch Childrens Research Institute, Parkville, Vic., Australia.
Alice G
AG
Ames
Alice
A
Jaques
Obioha C
OC
Ukoumunne
Alison D
AD
Archibald
Rony E
RE
Duncan
Jon
J
Emery
Sylvia A
SA
Metcalfe
D000293:Adolescent; D000328:Adult; D002755:Choice Behavior; D003697:Delphi Technique; D005260:Female; D005600:Fragile X Syndrome / Q000523:psychology*; D005820:Genetic Testing; D007722:Health Knowledge, Attitudes, Practice; D006579:Heterozygote; D006801:Humans; D007258:Informed Consent; D008875:Middle Aged; D010865:Pilot Projects; D011594:Psychometrics; D011795:Surveys and Questionnaires / Q000592:standards*; D055815:Young Adult