The evaluation for the Kiddy*-, Kid-, Kiddo-KINDLR versions is done analogously. *Please note the scoring differences for the Kiddy-KINDLR below.
The KINDLR questionnaires consist of a total of 24 items grouped into six subscales (with each subscale consisting of four items).
A total score can be calculated based on all 24 items (all subscales) of the KINDLR questionnaire.
STEP 1: ITEM RECODING
For most items, a higher score reflects a higher health-related quality of life (HRQoL). This means that they are positively worded and consistent with scoring (assigned value of a response option). However, some of the KINDLR items are worded inversely, meaning that a higher item score represents a worse health-related quality of life rather than a better one. To ensure that higher scores represent higher health-related quality of life here as well, these inversely formulated items must be recoded. That is, a score of 1 becomes 5, 2 becomes 4, 3 remains 3, 4 becomes 2, 5 becomes 1.
Procedure: At the beginning of the evaluation process, assign the numbers given in the table below to the selected answer options (for each item, i.e., for each question).
The items in question have already been recoded in the Excel table below.
Please note: The recoding of the negatively formulated items must be carried out regardless of which of the two evaluation procedures you choose, but in the case of using SPSS this is already done by the syntaxes provided.
For the item "...has my child felt ill" the questionnaire offers the answer options: 1 'never', 2 'rarely', 3 'sometimes', 4 'often' and 5 'always'. Thus, a high value of 5 in this item indicates that the child always felt sick. To ensure that a high value always represents a better quality of life, the item must be reversed.
This means: 1 becomes 5, 2 becomes 4, 3 remains 3, 4 becomes 2, and 5 becomes 1.
Thus, the original value of 5 in this item corresponds to the value 1 after recoding and indicates a reduced quality of life for the specific item.
Most common coding problems
The following guidelines are suggested:
Checking the data for typing errors and plausibility before starting the evaluation:
Sometimes respondents do not answer one or more items of a scale. However, the total value may only be calculated "by hand" if ALL items were answered by one person. Non-answered items may not simply be recalculated, so that a determination of the total sum value of the scale by means of imputation of the missing values is not recommended. For the "by hand" calculation, we therefore assume completely answered questionnaires.
However, it is possible to calculate the score on the basis of the available item answers with the help of the SPSS syntax. The algorithm recommended in the evaluation files replaces each missing value with a person-specific estimate, provided that the respondent has answered at least 70% of the items of a scale.
STEP 2: CALCULATION OF THE SCALE SUM SCORE
The total sum value can be calculated if at least 17 items were answered validly.
Addiotional scale "Disease"
In addition, an additional scale can be formed based on six items of the "Disease" module. The corresponding sum value can be calculated, provided that no more than one item is missing and the corresponding items have been reversed.
Scale sum score
For the formation of the scale sum score, the mean value is formed from the answered items of a scale (provided that information is not missing for more than 30% of the items). This mean value is then multiplied by the number of all items of this scale.
In order to calculate the sum value for the total scale, the mean value is also calculated in this case for all answered items of the questionnaire (provided that no more than 30% of the items are missing) and multiplied by the number of all items.
The transformed scale value (0-100) is based on the sum value and is calculated as follows:
transformed value = (sum value - lowest possible sum value )/(possible range of sum value)*100
For the Physical Well-Being subscale, a person reports the following values for the items that have already been reversed: Item 1: 4, Item 2: 3, Item 3: 2, Item 4: missing. The mean value of the scale ((4+3+2)/3) is 3. Multiplying by the number of items of the scale (3x4) results in a sum value of 12 for this respondent.
The scale transformed to values from 0 to 100 is calculated as follows for this case: For each of the four items, the lowest possible value is 1 and the highest possible value is 5. Consequently, the lowest possible sum value is 4. The possible range of the sum value is 16 (highest possible sum value (5 x 4 = 20) minus lowest possible sum value (4)). The transformed scale value here is therefore 50. Calculation: transformed value = ((12-4)/16)*100=50
The calculation of scale scores for the parent version of the Kiddy-KINDLR is essentially the same as described above for the other KINDLR versions. However, item 23 should not be recoded in this questionnaire version because it is not presented inversely.
Subscale "kiddy parents"
Furthermore, a specific subscale "kiddy parents" is made up of 22 additional items (items 25 to 46), which can be calculated if valid answers are available for at least 16 items. The following items should be repoled for this purpose: 25, 28, 31, 34, 36, 38, 39, 41, 44, 45, 46, 48, 49, 51, 52, 53.
In the self-report version of the Kiddy questionnaire, only the total score is formed from the 12 items presented and, if necessary, the additional scale "disorder". The inversely formulated items 1, 2, and 4 are to be reversed (illness module: items 14, 15, 17, 18, and 19). When inverting the items and calculating the sum value and the transformed value, the response options of the kiddy self-report version must be taken into account: 1 = never, 2 = sometimes, 3 = quite often.
Please note: The items in question have already been recoded in the Excel table above.