Table 3.
| a. Validity of recall of proximity to farmland stratified by case–control status and by calendar years of residence (1978/2001): sensitivity, specificity, and percentage match | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Controls (N = 347) |
Cases (N = 184) |
1978 |
2001 |
|||||||||
| 2001 | 1978 | Comparing | 2001 | 1978 | Comparing | Controls | Cases | Comparing | Controls | Cases | Comparing | |
| 2001, 1978 (P-value) |
2001, 1978 (P-value) |
(N = 347) | (N = 184) | controls, cases (P-value) |
(N = 347) | (N = 184) | controls, cases (P-value) |
|||||
| Specificity | 0.95 | 0.95 | 0.83 | 0.99 | 0.98 | 0.60 | 0.95 | 0.98 | 0.35 | 0.95 | 0.99 | 0.06 |
| Sensitivity | 0.55 | 0.54 | 0.90 | 0.61 | 0.39 | 0.02* | 0.54 | 0.39 | 0.05* | 0.55 | 0.61 | 0.51 |
| % Match | 80 | 80 | 0.92 | 87 | 74 | <0.01* | 80 | 74 | 0.14 | 80 | 87 | 0.04* |
| b. Validity of recall of proximity to farmland, influence of case–control status for 1978 and 2001: odds ratios | ||||||||
|---|---|---|---|---|---|---|---|---|
| 2001 |
1978 |
|||||||
| Unadjusted OR |
95% CI | Multivariate- adjusted OR* |
95% CI | Unadjusted OR |
95% CI | Multivariate- adjusted OR* |
95% CI | |
| Controls (N = 347) |
1.00 | 1.00 | ||||||
| Cases (N = 184) |
1.77 | 1.05, 2.97 | 1.74 | 1.01, 2.99 | 0.72 | 0.47, 1.11 | 0.74 | 0.47, 1.16 |
| c. Validity of recall of proximity to farmland, influence of years of residence (1978/2001) among cases and controls: odds ratios | ||||||||
|---|---|---|---|---|---|---|---|---|
| Cases (N = 184) |
Controls (N = 347) |
|||||||
| Unadjusted OR |
95% CI | Multivariate- adjusted OR* |
95% CI | Unadjusted OR |
95% CI | Multivariate- adjusted OR* |
95% CI | |
| 1978 | 1.00 | 1.00 | ||||||
| 2001 | 2.41 | 1.37, 4.22 | 2.36 | 1.33, 4.18 | 0.98 | 0.67, 1.43 | 0.97 | 0.66, 1.42 |
Specificity: among those participants classified by the satellite-derived land use file as living 40.25 miles from farmland, proportion of those self-reporting to be >0.25 miles from farmland.
Sensitivity: among those participants classified by the satellite-derived land use file as living r0.25 miles from farmland, the proportion of those self-reporting to be ≤0.25 miles from farmland.
*
P<0.05.
CI, confidence interval; OR, odds ratio.
*
Adjusted for gender, education, age, years at residence, geocoding accuracy, whether or not same residence for both years.
CI, confidence interval; OR, odds ratio.
*
Adjusted for gender, education, age, years at residence, geocoding accuracy, whether or not same residence for both years.