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I need to analyze data from the NHANES survey conducted by the U. S. government. I have the following instructions to analyze the data in SAS. Can SPSS Complex Samples do this, and if so, how? The code needed to specify sampling design parameters using SAS Survey procedures is described below. In this example, the SAS Survey procedure, proc surveymeans, is used and the name of the dataset is BP_analysis_Data. Proc surveymeans is being used as a generic example, but the strata, cluster and weight statements apply to all SAS Survey procedures. Step 1: Use data statement When using SAS Survey procedures, the input dataset must be identified. However, the dataset does not have to be presorted by the sample design variables as it does in SUDAAN. Rather, the design variables-strata and PSU-are specified in subsequent steps. Step 2: Use strata statement The strata statement names the variables that form the strata. For the Continuous NHANES the variable that identifies the sample strata is named sdmvstra. Step 3: Use cluster statement The cluster statement names the variables that identify the clusters in a clustered sample design such as NHANES. Since there is also a strata statement needed in NHANES, clusters are nested within the strata by SAS Survey procedures. In NHANES the variable that represents the sample clusters is named sdmvpsu (masked primary sampling units or PSUs). Step 4: Use weight statement In NHANES, a sample weight is assigned to each sample participant. The sample weight is a measure of the number of individuals in the target population that the sampled individual represents. Sample weights are needed to obtain unbiased estimates of population parameters when the sample participants are chosen with unequal probabilities. (See module on weighting for more details). The weight statement in SAS Survey procedures is required for all NHANES analyses. It identifies the sample weight. In this example, the MEC weight for 4 years of data (wtmec4yr) is used.
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Modified date:
16 April 2020
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swg21479072