Questionnaire construction

1. The theoretical and conceptual nature of dependence was reviewed. Items were developed based on the conception of dependence developed in the introduction.
2. Items resulting from step 1 were reviewed by clinicians working with people dependent on BZDs and their suggestions were implemented. At this point the new scale contained 68 items.
3. Items were randomly ordered and responses to 15 were reversed to reduce and assess for response bias.
4. The 68-item scale was piloted on people dependent on BZDs who were in treatment for anxiety disorders, and suggested changes were made.
5. A sample of people who had used BZDs more than seven times in the last three weeks was drawn and sampled on two occasions (waves one and two), as described in survey methods below. The 68 items included at this step are shown in Table 7.
6. Items 18 and 30 were excluded because the former was included to simplify the following 4 items and did not reflect dependence, and the later because it asked about withdrawal symptoms which were outside the focus of the scale.
7. The remaining 66 items were then reviewed to ensure that each reflected some aspect of the dependence concept outlined in the introduction. Items reflecting problems caused by use of BZDs were excluded in this step.
8. Correlation coefficients between each of the remaining items and the total score on the scale were calculated. Items with item-total correlations less than 0.4 were discarded following Nunnally's (1967) suggestions. Cronbach's [CronbachCronbach1951] coefficient alpha was also calculated as an index of the internal consistency of the scale.
9. Confirmatory factor analysis and exploratory principal components analysis were used to test the dimensionality of the resulting scale.

The steps used to construct the BDEPQ are described above in the methods section. The results of steps 7, 8 and 9 are described below and shown in Table 7.

 

 

Item Step

7 8 9

1. In the last month, have you felt that you would not sleep - 0.303 at all if you did not have a sleeping pill? 2. In the last month, have you taken another sedative or

tranquilliser as soon as the effects of the previous one - 0.590 - began to wear off?

3. Have you taken sedatives, tranquillisers or sleeping pills - 0.521 - in the last month because you like the way they make you feel?

4a. Have tranquillisers, sedatives or sleeping pills caused x you to feel sad, low, or depressed?

4b. How strong have these feelings been? x

5. In the last month, have you felt that you cannot face - 0.627 - anything out of the ordinary without a sedative or tranquilliser? 6. Have you been involved in accidents of any type (for

example cutting yourself or falling over) because you were x affected by sedatives, tranquillisers or sleeping pills?

7a. Have you had trouble with your memory because you x took tranquillisers, sedatives or sleeping pills?

7b. How severe have your memory problems been? x (Continued)

Notes: `x' indicates that the item was excluded in steps 7 or 9, and `-' indicates that the item was included. Numbers in the table represent item-total correlations.

 

Item Step

7 8 9

8. How much have you thought about sedatives, tranquillisers - 0.602 x or sleeping pills in the last month? 9. Do you keep spare sedatives, tranquillisers or sleeping

pills in different places (for example in your car or with - 0.388 your spouse) just in case you might need them?

10. Do you feel that you cannot get through the day without - 0.640 - the help of your sedatives or tranquillisers? 11a. In the last month, have you tried to cut down the

number of sedatives, tranquillisers or sleeping pills you - 0.399 have taken?

11b. Have you been successful when you tried? - 0.392

12. Do you need to carry your sedatives or tranquillisers with you? - 0.486 -

13a. Have tranquillisers, sedatives or sleeping pills caused x you to feel anxious, tense or keyed up?

13b. How strong have these feelings been? x

14. Have tranquillisers, sedatives or sleeping pills had - 0.392 less of an effect on you in the last month compared with when you first took them? (Continued)

 

Item Step

7 8 9

15. Have the pleasant effects of taking sedatives, tranquillisers - 0.421 x or sleeping pills changed since you first took them?

16. Have you gone to different doctors to get extra - 0.393 tranquillisers, sedatives or sleeping pills or to increase your supply?

17a. Have tranquillisers, sedatives or sleeping pills x caused you to feel paranoid, have strange ideas or see things that were not there?

17b. How strong have these feelings been? x

18a. When you started again how many sedatives, tranquillisers - 0.207 or sleeping pills did you need to get the same effect as before?

18b. When you started again did the same number of sedatives - 0.120 or tranquillisers have the same effect?

18c. When you started again did you feel the same urge - 0.161 or desire to take a sedative or tranquilliser?

18d. When you started again did you have the same - 0.152 difficulty controlling the number of sedatives, tranquillisers or sleeping pills you took? (Continued)

 

Item Step

7 8 9 19. Have sedatives, tranquillisers or sleeping pills

interfered with your life (for example stopped you x doing things you enjoy like sport or meeting people)? 20. Have you tried to reduce the number of sedatives,

tranquillisers or sleeping pills you take - 0.584 - because they interfered with your life? 21. Have you found that you needed to take more tranquillisers,

sedatives or sleeping pills to get the same effect - 0.428 - in the last month compared to when you first took them?

22. Do you need to take sedatives, tranquillisers or - 0.456 - sleeping pills to deal with the problems in your life?

23. How much time did you spend getting over the effects x of sedatives tranquillisers or sleeping pills in the last month?

24. Do you feel terrible if you do not take a sedative, - 0.579 - tranquilliser or sleeping pill?

25. Do you plan your day around when and where you can - 0.581 x take sedatives or tranquillisers? (Continued)

 

Item Step

7 8 9 26a. In the last month, have you been worried that your

doctor might not continue to prescribe the sedatives, - 0.510 - tranquillisers or sleeping pills you are taking?

26b. How strong has this worry been? - 0.520 -

27. Could you stop taking sedatives, tranquillisers or - 0.537 - sleeping pills tomorrow without any difficulties?

28. Do you count down the time until you can take your - 0.539 - next sedative, tranquilliser or sleeping pill?

29a. Have you experienced relief when you have taken sedatives, - 0.504 - tranquillisers or sleeping pills in the last month?

29b. How strong is that relief? - 0.536 -

30a. Have you taken another sedative, tranquilliser or - 0.439 - sleeping pill to reduce these unpleasant after-effects?

31. Have you drunk alcohol within a few hours of taking x sedatives, tranquillisers or sleeping pills? (Continued)

 

Item Step

7 8 9

32. Do you feel in control of the number of sedatives, - 0.273 tranquillisers or sleeping pills you have taken in the last month?

33. Have you driven a car or worked heavy machinery within x a few hours of taking sedatives, tranquillisers or sleeping pills?

34. Have you taken another person's sedatives, tranquillisers - 0.280 or sleeping pills because you felt like you did not have enough? 35. Have sedatives, sleeping pills or tranquillisers caused

you problems such as memory loss, drowsiness, problems at x work or with your family? 36. Have you reduced the number of sedatives, tranquillisers or

sleeping pills you take because of the problems - 0.352 they caused you? 37. In the last month, have you taken sedatives, tranquillisers or sleeping pills against your doctor's advice or

& - 0.483 - more frequently than recommended?

38. Are you concerned about the number of sedatives, tranquillisers - 0.519 - or sleeping pills you have taken in the last month? (Continued)

 

Item Step

7 8 9

39. Do you prefer one brand or type of sedative, tranquilliser - 0.175 or sleeping pill?

40. When you have been upset in the last month have you needed - 0.436 x to take sedatives or tranquillisers to calm you down or to sleep?

41. Have you taken more sedatives, tranquillisers or sleeping - 0.584 - pills in one day or night than you planned to?

42a. Have you found the effects of sedatives, tranquillisers - 0.422 - or sleeping pills pleasant?

42b. How strong is the pleasant feeling? - 0.496 -

43. Has your doctor asked you to reduce the number of - 0.377 tranquillisers, sedatives or sleeping pills you take?

44. Have you taken sedatives, tranquillisers or sleeping pills - 0.552 - for a longer period than you intended to when you started?

45a. Have you felt tense or anxious as your prescription for - 0.661 - sedatives, tranquillisers or sleeping pills began to run out?

45b. How strong have these feelings been? - 0.674 - (Continued)

 

Item Step

7 8 9

46a. Have you felt an urge or a desire to take sedatives, - 0.625 - tranquillisers or sleeping pills in the last month?

46b. How strong is that urge or desire? - 0.652 -

47. Have you taken sedatives, tranquillisers or sleeping - 0.475 - pills in the last month when you did not really need them?

48. I feel powerless to prevent myself taking a sedative or - 0.666 - tranquilliser when I am anxious, uptight or unhappy.

49. Successfully getting off sedatives, tranquillisers or - 0.024 sleeping pills is a matter of good luck.

50. Most of us are victims of forces and pressures that we x cannot control.

51. People who cannot control their use of tranquillisers or - 0.033 sedatives are just weak.

52. I would not be able to handle my problems unless I - 0.456 - take a sedative or tranquilliser.

53. I get so upset over small arguments, that I need to - 0.438 - take a sedative or tranquilliser.

Notes: `x' indicates that the item was excluded in steps 7 or 9, and `-' indicates that the item was included. Numbers in the table represent item-total correlations.

• Step 7: Excluding non-dependence items
• Step 8: Excluding items with low item-total correlation
• Step 9: Dimensionality of items