Worksheet with risk priority numbers (RPNs): first five ranks
| Failure mode | Effect | Severity | Possible causes | Occurrence | Detection | RPN | Rank |
| Degraded specimen | False negative | 4 | Time between sampling and processing too long (>6 days) because of late delivery to the pharmacy | 4 | 4 | 64 | 1 |
| Degraded specimen | False negative | 4 | Time between sampling and processing too long (>6 days) because of late delivery from pharmacy to laboratory | 4 | 4 | 64 | 1 |
| Degraded specimen | False negative | 4 | Time between sampling and processing too long (>6 days) because of delay in the laboratory | 4 | 4 | 64 | 1 |
| Mixed-up kits | Negative test result never communicated to the user | 3 | Wrong code because of manual entry by the pharmacist | 5 | 4 | 60 | 2 |
| Degraded specimen | False negative | 4 | Inadequate environmental temperature at user’s home | 3 | 4 | 48 | 3 |
| Degraded specimen | False negative | 4 | Inadequate environmental temperature during transport | 3 | 4 | 48 | 3 |
| Degraded specimen | False negative | 4 | Inadequate environmental temperature in the pharmacy | 3 | 4 | 48 | 3 |
| Degraded specimen | False negative | 4 | Inadequate environmental temperature in the wholesaler’s vehicle | 3 | 4 | 48 | 3 |
| Anonymous specimen | Positive test result never communicated to the user | 4 | The pharmacist provides the kit without using the programme’s management software | 4 | 3 | 48 | 3 |
| Anonymous specimen | Negative test result never communicated to the user | 3 | Wrong code because of manual entry by the pharmacist | 5 | 3 | 45 | 4 |
| Mixed-up kits | A person who has not done the test receives communication of a negative result by letter | 3 | Wrong code because of manual entry by the pharmacist | 4 | 3 | 36 | 5 |
| Mixed-up kits | A person who has not done the test receives communication of a positive result by phone call | 3 | Wrong code because of manual entry by the pharmacist | 4 | 3 | 36 | 5 |
| Anonymous specimen | Negative test result never communicated to the user | 3 | The pharmacist provides the kit without using the programme’s management software | 4 | 3 | 36 | 5 |
| Degraded specimen | False negative | 4 | Inadequate environmental temperature in the laboratory | 3 | 3 | 36 | 5 |