From: Population estimation and harm reduction among people who inject drugs in Addis Ababa, Ethiopia
| Characteristics | Frequency | Percent |
|---|---|---|
| Age at first injection | ||
| Below 20 years | 130 | 47.1 |
| 20–29 years | 119 | 43.1 |
| 30 years or more | 27 | 9.8 |
| Mean + SD | 22.1 + 6.1 | |
| The last injection | ||
| Today/yesterday | 45 | 16.3 |
| Within a week | 51 | 18.5 |
| Within a month | 44 | 15.9 |
| Frequency of injection | ||
| Daily to 2–3 per day | 29 | 33.0 |
| Once in a week to a month | 168 | 60.9 |
| Less frequent (> 3 months) | 17 | 6.2 |