Table III.

Choices in designing studies of the prevalence of use of medically assisted reproduction.

Broad category	Specific category	Choice
Study design	Location of study	One country versus multi-country
	Respondent group	Women versus men versus both
		Individual versus couple
	Time focus	Current prevalence versus lifetime prevalence
	Type of study	Cross-section versus repeated cross-section versus longitudinal
Denominator for equation (population at risk)	Population	Infertile versus people of reproductive age
		Heterosexual individuals/couples, singles, same-sex individuals/couples
	Measure of infertility	Medical criteria versus self-perception or self-identification
		Infertile with intent versus all infertile
	Further sample specifications	Based on sociodemographic variables such as marital status, parenthood, education/occupation, age
Numerator for equation	Measure of treatment	Single cutoff point versus multi-stage measure
	Threshold for help-seeking	Talk to doctor versus tests versus treatment
		ART versus any treatment