A multistage sampling design that combined multicluster (West Anatolia vs. Central Anatolia regions and rural vs. urban residents) and simple random sampling methods were used for the sample selection.
The KNHANEs has a stratified multistage sampling design that examines all household members above the age of one.
The NHIS, one of the oldest US national health surveys, has a complex multistage probability design that uses clustering and stratification with oversampling of selected population subgroups [ 10, 11].
During each year, a sample representing the civilian, noninstitutionalized US population aged ≥ 18 years was selected by using a complex multistage sampling design that involves stratification, clustering, and oversampling.
The study used a multistage sampling design that first selected a random sample of enumeration areas and then selected a random sample of households systematically from a household listing of all households in the enumeration area.
There is no universally accepted definition of these designs, but a working definition might be "a multistage study design that uses accumulating data to decide how to modify aspects of the study without undermining the validity and integrity of the trial".
The LSOA II followed a stratified, multistage probability design that permitted continuous sampling of the target population.
NAMCS utilized a multistage probability design that involved probability samples of primary sampling units (PSUs), physician practices within PSUs, and patient visits within practices [ 17].
Briefly, the NHIS survey comprises a complex multistage area probability design that provides a representative sample of US households from all 50 states and the District of Columbia.
