Figure	CKD—Questionnaire		GP—Questionnaire
	Question	Answer	Question	Answer
Figure 1	Do you use drugs for pain relief?	a. yes b. no	Do you use drugs sold over-the-counter for pain relief?	a. yes b. no
Figure 2	Which of the listed drugs are you taking? (Please indicate from the most used)	a…. b… c…	Please provide the names of analgetic drugs you used?(from the most to the least frequently used)	a…. b… c… d… * c and d were merged in calculations
Figure 3	You take them (painkillers) because of: (Select all appropriate variants of the answer, please) *	a. toothache c. headache d. joint pain e. menstrual pain f. back pain g. other……………….? * according to patient’s answers in variant ‘other’ we categorized the data as follow: joint and muscle pain; fever/infection; headache; spinal pain; toothache; abdominal pain; other	You take them (painkillers) because of: (you may select more than one answer) *	a. abdominal pain c. back pain d. joint pain e. toothache f. fever g. to improve the well-being h. other…………?
Figure 4	When did you take over-the counter painkiller for the last time? (Mark one answer, please)	a. today b. yesterday c. this week d. this month e. during the last 6 months f. I didn’t take analgesic drugs in the last 6 months g. hard to say, I don’t remember * answer ‘g’ was not included in calculations	When was the last time you took over-the-counter painkiller?	a. today b. yesterday c. this week d. in the last month e. during the last 6 months f. I didn’t take analgesic drugs in the last 6 months
Figure 5	Do you think that the painkillers may cause side effects? (Mark one answer, please)	a. definitely yes b. rather yes c. sometimes d. rather no e. certainly not f. hard to say, I don’t know * a, b, c and d, e, f were merged separately in calculations	Do you think that the painkillers may cause side effects?	a. yes b. no
Figure 6	Do you think that advertisement of painkillers reliably informs you about the effectiveness of the drug? (Mark one answer, please)	a. yes, always b. yes, often c. sometimes d. no, never e. hard to say * only definitive answers were compared	How strong do you believe in different sources of information * (advertisement/media) about analgesic drugs? Please grade your answers from 1 to 5.	1—I do not believe at all 2—I believe a little 3—I believe quite a lot 4—I believe very much 5—I believe totally
Figure 7	Do you consult the choice of painkiller with your doctor? (Mark one answer, please)	a. yes, always b. yes, often c. occasionally d. no, never * a and b were merged in calculations	Do you consult the choice of painkiller with your doctor?	a. always b. sometimes c. never
Table 1, Table 2, Table 3 and Table 4	Metrics
	Gender	a. F b. M	Please, indicate your gender	a. F b. M
	Date of birth (day/month/year)	……..	Please, provide your birth date (day/month/year)	……..
	What diseases do you have? (Select all appropriate variants of the answer, please)	a. hypertension b. diabetes mellitus c. gastric ulcers disease and/or duodenal ulcer d. cardiovascular diseases (ischemic heart disease, myocardial infarction) e. kidney failure f. other ………?	Which of the following diseases do you suffer from? (you may indicate more than one answer)	a. hypertension b. diabetes c. gastric and/or duodenal ulcer disease d. cardiovascular diseases (coronary disease, myocardial infarction) e. chronic renal disease f. chronic liver disease g. other ………?
* do not need any explanation, this is information from author about how the questionnaires were interpreted.