I am not able to answer the question about the attention check questions because I am not familiar with them.

In a survey questionnaire for a research topic where the target survey population may not be familiar with the definitions used by the survey, it is always recommended that all the variables should be clearly defined and unambiguous. This is because a questionnaire is a universal tool that is commonly used to collect relevant and intended information from the respondents of a survey. The researchers often use the questionnaire to collect the relevant information from the respondents in order to measure each of the variables or items constituting its domain of interest, and also for addressing the objectives of a research study. In fact, in most of the complicated surveys such as a patient registry, the questionnaire will usually be accompanied by a variable dictionary which provides each and every variable with a specific definition (NHAM, 2015).

However, we must also bear in mind that whenever new research is being conducted using patient registry data, it is usually advisable to first understand the scope of a registry is by reviewing its Case Report Form (CRF). The CRF is a structured questionnaire designed to collect information from the patients. It is a questionnaire where specific details of each individual patient including his/her profile, history of disease, treatment and outcomes are recorded. The researcher should also carefully examine the design of a CRF, including the definitions of all its variables, in order to assess whether the data collected by the CRF meet the minimum data requirement set by the researchers. It is also strongly recommended for both the CRF and its accompanying instruction manual to be kept for future reference. If the researcher has any doubts about the data collection procedures of a registry and/or the data collected by its CRF, it would be in his/her best interest to seek for a clarification with the person in-charge of data management for the registry data at the earliest opportunity. Next, the researcher should then determine whether the data collected by the registry will be able to address all primary and secondary research objectives of the new research study. This will involve a careful assessment of whether the registry is collecting all the necessary data which are required by the researchers and also whether the sample size deployed by the study will be adequate for fulfilling all research objectives of the study. The researcher should also carefully screen through the CRF to confirm if all the variables that will be collected by the CRF are actually reported in the registry database.

Apart from the above-mentioned considerations, it is also necessary to consider the sample size requirements for conducting a registry study. This is to ensure that the minimum power of the new registry study (that involves retrieving relevant registry data for research purposes) will realistically be achieved. If the study will not be collecting registry data, but is merely conducting a survey by using a questionnaire; it is nevertheless still necessary to carefully determine the minimum sample size requirement for conducting the survey via a questionnaire.

If your new survey involves collecting relevant data from either a questionnaire or from a patient registry, it is recommended to refer to any of the three attached e-books if you have any queries about how to analyze or interpret the data obtained from a questionnaire or a patient registry.