Methodological considerations
The present study was using a randomized study design. The dropout rate (enrolled patients not performing the telephone interview) in the current study was higher than anticipated (39%, 17 and 81 in the control and intervention group respectively) limiting the power to identify statistically significant differences. Applicable to both groups, the high dropout rate was mainly due to patients not answering their phone or being readmitted. For future studies, a suggestion to minimize the high dropout rate could be to schedule follow-up telephone calls or to arrange a personal meeting in the patients’ private homes and enroll patients who are less prone to be readmitted.Another limitation in the current study concerns the interview guide that includes some questions that are not fully validated. However, most of the questions in the interview guide were adopted word-for-word from other studies ensuring that the majority of the questions had been tested by other researchers beforehand [The clinical impact of the helpline responses was assessed by two clinical pharmacists working at the MIC. This is a potential bias, and it would have strengthened the data analysis if an impartial party had analyzed the responses.Another methodological consideration in the current study is the risk of respondent’s social desirability bias where respondents may respond in a way they think the investigator wants to hear and hereby present themselves in the best possible way [Further, there is a risk of recall bias, which is a systematic error that occurs when the participants do not recall or remember previous experiences accurately or omit details related to the topic of interest [Participants in the current study were included from two departments, an emergency department and a department of respiratory medicine. Thus, the present results are most probably only representative of similar clinical settings. Indeed, future studies should investigate other clinical settings.