Table 4.
Distribution of respondents with episodic (EM) and chronic migraine (CM) by study module.
| Time of emailing | Module(s) | EM respondents, n (%) | CM respondents, n (%) | Total respondents,a n |
|---|---|---|---|---|
| Month 0 (Baseline) | Screening, Core (wave 1), and Barriers to Care | 15,313 (91.2) | 1476 (8.8) | 16,789c |
| Month 1 (resampled in month 11)e | Comorbidities/endophenotypes | 11,699 (91.3) | 1111 (8.7) | 12,810 |
| Month 2 (resampled in month 7)e | Family Burden Module (Proband)b | 11,938 (91.4) | 1126 (8.6) | 13,064 |
| Month 3 | Snapshot (wave 2) | 9022 (92.6) | 719 (7.4) | 9741c |
| Month 3 (resampled in month 8)e | Family Burden Module (Partner) | 3642 (90.6) | 380 (9.4) | 4022 |
| Month 4 (resampled in month 8)e | Family Burden Module (Child) | 1536 (88.6)d | 197 (11.4)d | 2140d |
| Month 6 | Core (wave 3) | 6990 (93.0) | 527 (7.0) | 7517c |
| Month 9 | Snapshot (wave 4) | 5956 (93.6) | 406 (6.4) | 6362 |
| Month 12 | Core (wave 5) | 5502 (93.0) | 413 (7.0) | 5915c |
Total number of respondents who completed each of these modules.
Family Burden Module was supplemented with additional respondents who were over quota but otherwise qualified per the CaMEO Study criteria (see Figure 2).
Includes those who completed each wave (Snapshot/Core Module). A subset of this population completed all 5 waves (Core/Snapshot; n = 3626).
The total number of children responding to the Family Burden Module (Child version) was 2140, representing 1733 unique probands. Rates of EM and CM respondents were calculated based on the number of unique probands (n = 1733), since some had multiple children respond to the survey.
A fraction of the sample did not complete either the Family Burden or Comorbidities/endophenotypes modules during stage 2, and were resampled during stage 3 to minimize nonresponse.