Table 1.
Demographic characteristics of the prescription data
| Characteristics | N (%) Total=529 990 |
| US geographical regions* | |
| Midwest | 214 451 (40.5) |
| Northeast | 126 751 (23.9) |
| South | 109 441 (20.6) |
| West | 74 082 (14.0) |
| Outside of the USA | 236 (0.0) |
| Top 5 drug classes | |
| Agents acting on the renin–angiotensin system | 77 315 (14.5) |
| Lipid-modifying agents | 73 509 (13.9) |
| Drugs used in diabetes | 56 179 (10.6) |
| Psychoanaleptics | 49 382 (9.1) |
| Drugs for obstructive airway diseases | 31 475 (5.9) |
| Median (1st–3rd quartile) no of words in directions from e-prescriptions | 8 (6–10) |
| Median (1st–3rd quartile) no of words in directions from prescription labels | 8 (7–9) |
| No of unique prescription directions before transcription | 123 746 |
| No of unique prescription directions after transcription | 88 249 |
*5029 (0.9%) of national provider identifier numbers could not be matched using the November 2018 United States National Plan and Provider Enumeration System national provider identifier download files.