Volume 10, Number 6—June 2004
Research
Sporadic Cryptosporidiosis, North Cumbria, England, 1996–2000
Stella Goh*, Mark Reacher†
, David P. Casemore‡, Neville Q. Verlander†, Rachel Chalmers§, Margaret Knowles¶, Joy Williams*, Keith Osborn#, and Sarah Richards**
, David P. Casemore‡, Neville Q. Verlander†, Rachel Chalmers§, Margaret Knowles¶, Joy Williams*, Keith Osborn#, and Sarah Richards**Table 1
Recruitment and reasons for exclusion from study, United Kingdom (UK)
| Exclusion criteria | No. (%) excluded |
|---|---|
| Case-patients (n = 207) | |
| Refusal to participate | 1 (0.5) |
| Could not complete adequate interview | 1 (0.5) |
| Did not respond to letters or phone calls | 2 (1.0) |
| Not meeting the study case definition | |
| No history of diarrhea | 1 (0.5) |
| Mixed enteric infection | 1 (0.5) |
| Secondary case | 36 (17.4) |
| Travel outside the UK in 14 days before onset | 8 (3.9) |
| Travel in UK outside study area for >7 nights in the 14 days before onset | 1 (0.5) |
| Visitor to study area | 1 (0.5) |
| Residence outside study area | 1 (0.5) |
| Case-patient or household member previously interviewed as case-patient or control | 2(1.0) |
| Total potential cases excluded |
55 (26.6) |
| Total cases enrolled | 152 (73.4) |
| Controls (n = 778) | |
| Refusal to participate in interview | 23 (3.0) |
| Unavailable at requested interview times | 125 (16.1) |
| Said interview times were not convenient | 35 (4.5) |
| Subtotal: refused, unavailable for interview | 183 (23.5) |
| Address not found | 3 (0.4) |
| History of diarrhea | 46 (5.9) |
| Travel outside UK in the 14 days before interview | 8 (1.0) |
| Travel in UK outside study area for >7 nights in the 14 days before interview | 2 (0.3) |
| Not resident in study area in the 14 days before interview | 3 (0.4) |
| Moved from study area | 27 (3.5) |
| Resident outside study area | 2 (0.3) |
| Control or household member already interviewed as a case-patient or control | 7 (0.9) |
| Subtotal: did not meet study control definition | 95 (12.2) |
| Interview cancelled by study team because three controls already enrolled for associated case | 19 (2.4) |
| Interview cancelled by study team as potential control found to be in wrong age group | 9 (1.2) |
| Reason for exclusion not recorded | 3 (0.4) |
| Subtotal: not enrolled for administrative reasons or reason not recorded | 31 (4.0) |
| Total potential controls excluded |
312 (40.1) |
| Total controls enrolled | 466 (59.9) |
