Reliability of the initial items included in the scale was variable, suggesting the need for refinement of the scale; this led to selection of items that showed relevance, specificity, and item-total correlation.
Another limitation was that the selection of the initial items to include in the ABC measure was hampered by lack of preexisting validated measures of cancer beliefs.
Development of the initial items for the PedsQL™ EoE Module began in 2008.
Thirty-five items from the Cancer Attitudes Inventory (CAI) were also included in the initial item pool [ 31].
Items assessing pity were included in the initial item pool because previous studies on stigma had included this construct.
However, when the item pool was developed some items with overlapping content were retained in the initial item pool as there was no criteria on which to judge which items to retain or delete.
Correct translations were then coded for whether they were the expected translation (i.e., that provided by Nishimoto et al., 2005, for concrete items [the picture naming stimuli], or the translation assigned in the initial item selection stage e.g., ball ボール or an alternative translation).
To assess item characteristics and the measurement model (scaling) for the measure, the following tests were performed: For item reduction, both item psychometric properties and conceptual importance were taken into consideration in making retention/deletion decisions for the initial item pool.
The initial items for inclusion in the preliminary "Enhancing transparency in reporting the synthesis of qualitative research (ENTREQ) Statement" were generated inductively from guides to synthesising qualitative health research [ 1, 10], seminal methodology papers [ 4, 11, 12, 22- 24] and the authors' experience in conducting and appraising qualitative syntheses (AT, KF, EM,).
In addition, the recalibrated item parameters fell within ± 0.5 logit of the initial item location for each item.
Eight items of the initial item pool (181 items) were excluded due to low factor loadings.
