Differences in scope, collection methodology and design may account for this variation and comparisons between collections should be made with caution. The questions asked in the surveys also differ and therefore results from the surveys are not directly comparable. It is important to keep this in mind when considering data from each of the surveys—results that may initially seem to contradict one another may reflect the different methodology used or be applicable to different groups within the population.
Data sources are often selected based on which data source was considered the ‘best fit’ to analyse trends over time for a particular topic/project. Each of these data sources has differing strengths and the fact a data source was selected for use does not imply that it is a ‘better’ data source, only that it was considered more appropriate for the particular analysis for which it was used. Table N1 below summarises the differences between the National Health Survey and the National Drug Strategy Household Survey.
For more information on the strengths and limitations of the AIHW National Drug Strategy Household Surveys see 2013 National Drug Strategy Household Survey (NDSHS).
For more information on the strengths and limitations of the ABS National Health Surveys, see Australian health Survey: Users’ Guide, 2011–13.