Table 4 Summary of key modifications made to the PAD-O following each round of interviews

Training Guide

A section in the Training Guide outlining how to answer the diary was updated to include the additional example of “family friends” as people that caregivers can receive input from regarding their child’s asthma symptoms

Relevant Training Guide sections were updated to allow for both single and multiple-observer completion, providing greater flexibility and inclusivity of a broader range of family circumstances in future clinical trials. Multiple-observer completion allows for a maximum of 2 observers to share completion of the PAD-O, if single observer completion is not feasible

As for the PAD-C Training Guide, wording in the PAD-O Training Guide was updated to reflect the possibility that diary answers could be shared with the doctor

Instructions

There were no key modifications made to the PAD-O instructions following Round 1 caregiver interviews

The Morning Diary and Evening Diary instructions were updated to allow for the possibility of both single and multiple-observer completion, to align with the updates to the Training Guide

As for the instructions in the PAD-C Bedtime Diary, instructions in the PAD-O Evening Diary were updated to specify “bedtime” as the end of “today” more clearly

Core items

There were no key modifications made to the PAD-O core items following Round 1 caregiver interviews

The item assessing cough intensity was updated to an alternative item and response scale tested in Round 2 interviews including the terminology “severe” based on better participant understanding

As for the PAD-C core items, one of the response options for the global nighttime asthma symptom severity item was updated to specify asthma symptoms

There were no key modifications made to the PAD-O core items following Round 3 caregiver interviews

Supplementary items

As for the child supplementary items, new caregiver supplementary items assessing whether the child has a nebulizer were added to both diaries and instructions for skip logic were included and tested

Wording in the caregiver nebulizer items was updated; an alternative term for nebulizer was added

As for the child supplementary items, relevant recall periods were added to items assessing amount of rescue inhaler used and number of times nebulizer used. The response option and item wording were also updated to clarify that participants should report the total number of puffs or times used

As for the child supplementary items, an alternative term for “rescue” was removed from the caregiver rescue inhaler items due to lack of understanding. A definition of rescue inhaler was also added to the caregiver items

As for the child supplementary items, the caregiver nebulizer items were updated to ensure that they collect data on rescue medication use only as some participants in Round 2 interviews stated that nebulizers were used for both rescue and maintenance medication

As for the child supplementary items, wording included in the caregiver nebulizer items specifying rescue medication use was simplified to similar wording that was tested and well understood in Round 2 interviews

Developmental items

The response options for the sources of information item were updated to include an additional response option for input received from family friends. Response options that were unlikely to be used during the relevant time period were removed from the Morning Dairy

As for the child developmental items, one of the response options for the caregiver global daytime asthma symptom severity item was updated to specify asthma symptoms

It was agreed to remove the caregiver developmental item from the Morning Diary asking whether caregivers check on their child during the night, as interview data showed that most caregivers regularly check on their child at night regardless of asthma symptoms

The response options for the sources of information items were updated to remove an open-ended “Other” response option and to rearrange the order of the response options to reflect frequency of use by participants throughout all 3 rounds of interviews