INTERPRETATION OF HAEAMO-QoL SCORES
Scale-based scoring: Haemo-QoL scale scores and total scores are available after scoring. Using standardised scores, each patients subscale score can be compared across subscales and a total score can be identified with the anchors of the scale. Scores reaching 3 (for children age group I) or 5 (for age groups II and III) suggest high impairment in quality of life, while scores nearing 1 suggest low impairment and therefore a positive quality of life rating. Using transformed scales ranging from 0 to 100, the similarity with percent values is helpful for the interpretation; again high scores (nearing 100) indicate a low quality of life rating. Raw scores are more difficult to interpret, because the range of the subscale –which differs from subscale to subscale depending on the number of items- has to be included.

Reference groups based scoring. In addition to an interpretation according to the location of the subscale score within the range of possible values, a comparison with reference scores is possible (e.g. as described in the Haemo-QoL final report. If questionnaire data are computer inputted and scored, this data bank can be used to statistically test differences in scores according to patient groups (e.g. according to treatment strategies) or over time (eg. before and after change of treatment). Using variance analytical or correlational statistical procedures, the relationship between patient self report and parent rating can be examined.

Evidence-based scoring. Since the Haemo-QoL database is still growing, clinical information is not yet sufficient to define cut-off scores for critical quality of life impairment. Also the prognostic benefit of a subscale or total score remains to be researched in upcoming studies.