Use of short-term counts and surveys
The main concern with short-term counts is that they do not accurately capture variations in cycling over time (i.e. time of the day, day of the week, season, as well as weather). If you count on a sunny day, you may see larger numbers than on a rainy day. Since HEAT assumes that the entered data reflect long-term average levels of cycling, data from short-term counts will distort the results.
This issue will mainly affect single facility evaluations (e.g. a footpath, or a bridge) where counts are conducted on the facility itself, or community-wide evaluations that are based on surveys conducted only during a certain time of the year.
Not affected by this issue are assessments based on large surveys, which are conducted on a rolling basis (e.g. national household surveys), or automated continuous counts.
Short term counts may also be adjusted for temporal variation, to better reflect long term levels of cycling. An example for how this can be done is provided by the US National Bicycle and Pedestrian Documentation Project
Use of data from few locations
Use of trip or count data