Review of ehrQL code

[alschaffer]

Hi Milan, here is my ehrQL code that I would appreciate if you could review. FYI study protocol is here.

This is the dataset definition:

• https://github.com/opensafely/waiting-list/blob/main/analysis/dataset_definition_clockstops.py

Measures code (Note - some explanation is needed. Here, I am measuring the opioid prescribing rate in each week of the study period. There are three key periods: 6 months prior to waiting list start; while on the waiting list; and 6 months after waiting list end. However, the start/end dates for each individual differs and Measures only works with calendar dates. Therefore, I standardised the relevant dates for each of the three periods relative to a random date [2000-01-01]).

• For any opioid prescribing: https://github.com/opensafely/waiting-list/blob/main/analysis/measures_any_opioid.py
• For high dose, long-acting opioid prescribing (same as above, just different codelist): https://github.com/opensafely/waiting-list/blob/main/analysis/measures_hi_opioid.py