Table 2.
Baseline Item Distributions and Pre- and Post-Intervention Differences: Draft NRT Necessity Belief Items
| Draft NRT necessity belief items | Baseline (N = 39) | Pre-post intervention (N = 24) |
Resulting item removals and amendments | |||
|---|---|---|---|---|---|---|
| Mean(SD) | Mean(SD) pre | Mean(SD) post | Mean(SE) change | p a | ||
| n1. Using NRT instead of smoking would improve my baby’s health | 4.5(0.72) | 4.5(0.72) | 4.7(0.70) | 0.13(0.13) | .317 | Amendment: baseline agreement >4. Stronger wording: “My baby’s health would improve if I used NRT” |
| n2. Quitting smoking would be impossible for me without NRT | 4.0(0.90) | 4.0(0.83) | 4.2(0.82) | 0.17(0.21) | .392 | Item unchanged: similar wording to a validated BMQ item |
| n3. NRT would help me to avoid smoking in places and situations where I would usually smoke | 3.8(0.81) | 3.9(0.88) | 4.3(0.76) | 0.42(0.13) | .008 | Amendment, to avoid ambiguity: “NRT will help me avoid smoking in places and situations where I’d usually smoke” |
| n4. NRT would relieve the discomfort (withdrawal symptoms) of quitting smoking | 4.0(0.58) | 4.2(0.56) | 4.1(0.93) | −0.08(0.17) | .589 | Amendment, to avoid ambiguity: “NRT will relieve my discomfort from quitting smoking (withdrawal symptoms)” |
| n5. Using NRT instead of smoking would improve my health | 4.4(0.64) | 4.5(0.66) | 4.7(0.70) | 0.17(0.16) | .305 | Amendment: baseline agreement >4. Stronger wording: “My health would improve if I used NRT” |
| n6. For NRT to work, I’d only need to take it when I feel like I need itb | 3.1(0.84) | 3.1(0.93) | 1.9(0.88) | −1.17(0.22) | <.001 | Amendment: “For NRT to work, I’d only need to use it when I feel like I need it”b |
| n7. If my quit attempt is going well early on, I would want to test whether I could do without my NRTb | 3.1(1.06) | 3.1(1.10) | 2.7(1.05) | −0.42(0.25) | .095 | Amendment, to simplify: “If my quit attempt is going well, I’d want to test if I could do without NRT”b |
| n8. NRT would help me to avoid smoking when I’m stressed | 3.6(0.85) | 3.5(0.88) | 3.8(0.94) | 0.21(0.19) | .268 | Amendment, to avoid ambiguity: “NRT will help me avoid smoking when I’m stressed” |
| n9. NRT would control my cravings to smoke | 3.6(0.64) | 3.6(0.72) | 4.3(0.68) | 0.67(0.16) | .001 | Amendment, to avoid ambiguity: “NRT will control my cravings to smoke” |
| n10. NRT will not improve my chances of quitting smoking during pregnancyb | 2.6(0.99) | 2.4(1.06) | 1.8(1.06) | −0.58(0.33) | .089 | Amendment, to reduce cognitive load; “not” removed: “NRT will improve my chances of quitting smoking in pregnancy” |
| n11. NRT only works if it is taken regularly (N = 38) | 3.7(0.67) | 3.8(0.74) | 4.5(0.51) | 0.79(0.16) | <.001 | Item removed: “don’t know” from one participant; high proportion of “3” responses; similar meaning to item “n6” |
| n12. NRT will help me to quit | 4.2(0.47) | 4.3(0.46) | 4.5(0.66) | 0.21(0.15) | .166 | Item removed: baseline agreement >4; similar meaning to item “n10” |
| n13. I would no longer need NRT after a few weeks of using itb | 2.7(0.68) | 2.7(0.76) | 1.8(0.64) | −0.83(0.18) | .001 | Amendment, to simplify: “I’d only need to use NRT for a few weeks”b |
| n14. NRT should be taken for at least 8 weeks (N = 38) | 3.4(0.60) | 3.5(0.59) | 3.9(0.93) | 0.38(0.19) | .067 | Item removed: “don’t know” from one participant; high proportion of “3” responses; similar meaning to item “n13” |
Item n2 was adapted directly from a Beliefs about Medicines Questionnaire (BMQ) necessity belief (“My life would be impossible without my medicines”); items n1 and n5, and items n3, n4, n8–10, and n12 loosely reflect BMQ necessity beliefs (respectively, “My health, at present, depends on my medicines” and also “My health in the future will depend on my medicines” and “My life would be impossible without my medicines”); items n6, n7, n11, n13, and n14 are novel. NRT = nicotine replacement therapy.
aFrom paired Wilcoxon tests (2-tailed, α = 0.05).
bReverse-scored item, where agreement indicates lack of perceived need for NRT. A score of 5 is transformed to 1, a score of 4 to 2, and so on.