Table 2 Weighting schemes
From: Inter-rater reliability of the QuIS as an assessment of the quality of staff-inpatient interactions
Weighting scheme | + s | + c | N | - p | - r | COMMENTS | |
|---|---|---|---|---|---|---|---|
Unweighted | + social | 1 | Ignores the degree of misclassification between categories | ||||
+ care | 0 | 1 | |||||
Neutral | 0 | 0 | 1 | ||||
- protective | 0 | 0 | 0 | 1 | |||
- restrictive | 0 | 0 | 0 | 0 | 1 | ||
Linear | + social | 1 | Standard weights 1 for ordinal variables in Stata. Weights 1-|i-j|/(k-1), where i and j index the rows and columns, and k the number of categories | ||||
+ care | 1 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 1 | 1 | ||
Quadratic | + social | 1 | Standard weights 2 for ordinal variables in Stata. Weights 1 - {(i-j)/(k-1)}2. | ||||
+ care | 0.75 | 1 | |||||
Neutral | 0.5 | 0.75 | 1 | ||||
- protective | 0.25 | 0.5 | 0.75 | 1 | |||
- restrictive | 0 | 0.25 | 0.5 | 0.75 | 1 | ||
A: Weights given to neutral compared to a positive or negative = 0.5, assuming that misclassification between the positives is equal to misclassification between the negatives. | |||||||
Weighted A1 | + social | 1 | All possibilities from weighting misclassification between the two positives and the two negatives as 1 (will be the same as having only three categories, positive neutral and negative) to weighting it as 0.6. Weighting scheme 4 has a weights of 0.75 (half way between .5 and 1) | ||||
+ care | 1 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 1 | 1 | ||
Weighted A2 | + social | 1 | |||||
+ care | 0.9 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.9 | 1 | ||
Weighted A3 | + social | 1 | |||||
+ care | 0.8 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.8 | 1 | ||
Weighted A4 | + social | 1 | |||||
+ care | 0.75 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.75 | 1 | ||
Weighted A5 | + social | 1 | |||||
+ care | 0.7 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.7 | 1 | ||
Weighted A6 | + social | 1 | |||||
+ care | 0.6 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.6 | 1 | ||
Weighting scheme | + s | + c | N | - p | - r | COMMENTS | |
B: Weights using less than 0.5 for neutral compared to a positive or negative and assuming that misclassification between the two positives is equal to misclassification between the two negatives | |||||||
Weighted B1 | + social | 1 | |||||
+ care | 0.66 | 1 | |||||
Neutral | 0.33 | 0.33 | 1 | ||||
- protective | 0 | 0 | 0.33 | 1 | |||
- restrictive | 0 | 0 | 0.33 | 0.66 | 1 | ||
Weighted B2 | + social | 1 | |||||
+ care | 0.5 | 1 | |||||
Neutral | 0.25 | 0.25 | 1 | ||||
- protective | 0 | 0 | 0.25 | 1 | |||
- restrictive | 0 | 0 | 0.25 | 0.5 | 1 | ||
Weighted B3 | + social | 1 | |||||
+ care | 0.5 | 1 | |||||
Neutral | 0 | 0 | 1 | ||||
- protective | 0 | 0 | 0 | 1 | |||
- restrictive | 0 | 0 | 0 | 0.5 | 1 | ||
C: Weights assuming that misclassification between the two negative categories is less important than misclassification between the two positives and varying the neutral weights | |||||||
Weighted C1 | + social | 1 | |||||
+ care | 0.5 | 1 | |||||
Neutral | 0.25 | 0.25 | 1 | ||||
- protective | 0 | 0 | 0.25 | 1 | |||
- restrictive | 0 | 0 | 0.25 | 0.75 | 1 | ||
Weighted C2 | + social | 1 | |||||
+ care | 0.6 | 1 | |||||
Neutral | 0.4 | 0.4 | 1 | ||||
- protective | 0 | 0 | 0.4 | 1 | |||
- restrictive | 0 | 0 | 0.4 | 0.8 | 1 | ||
Weighted C3 | + social | 1 | |||||
+ care | 0.66 | 1 | |||||
Neutral | 0.5 | 0.5 | 1 | ||||
- protective | 0 | 0 | 0.5 | 1 | |||
- restrictive | 0 | 0 | 0.5 | 0.83 | 1 | ||