Main Activity Filter
Users may select any combination of activities from the activity hierarchy to create time use variables. For more information about specific activity categories, click on category names in the activity hierarchy. For more information about this variable, including comparability, see MAIN.
Users may notice that the activity codes used to create time use variables in the AHTUS-X system are different from those available in MAIN. The difference is simply in the codes assigned to specific values. For example, all Personal Care activities are preceded with 01 in the activity variable used to create time use variables via AHTUS-X. So 0101 (General or other personal care) directly corresponds to MAIN code 01 for general or other personal care.
Detailed information about how original activity codes are combined in the harmonization process are available in documentation provided by the Centre for Time Use Research, University College London.