Table 3

Descriptive statistics and paired statistical comparisons for subjective effect measures from participants (n=34 unless specified) smoking the RWP in three configurations: control, bubble diffuser and electric

Mean±SDP value for statistical comparison*
ControlBubble diffuserElectricBubble diffuser versus controlElectric versus control
Minnesota Nicotine Withdrawal Scale (MNWS) Difference Score (postsmoking minus presmoking)†‡
 Urges to smoke a waterpipe−16.9±28.1 −30.7±32.9 −25.5±29.9P<0.01ns
 Irritability/frustration/anger−3.3±12.5−0.7±17.60.6±5.6 ns ns
 Difficulty concentrating4.7±19.96.7±21.91.6±15.5nsns
 Craving a waterpipe/nicotine−15.6±22.9 −27.0±29.5 −24.9±28.9 P<0.05P<0.10
 Drowsiness11.6±29.32.6±26.7 −4.0±22.1 nsP<0.05
 Depression/feeling blue1.8±14.7−2.6±10.10.3±12.7nsns
 Desire for sweets5.5±15.6 −1.7±8.5 −0.4±10.6 P<0.05P<0.05
Waterpipe-modified Brief Questionnaire on Smoking Urges (QSU-brief); difference score (postsmoking minus presmoking)
 Intention to smoke (factor 1)−2.0±1.5§ −2.5±1.6 −2.2±1.6P<0.10ns
 Relief from withdrawal (factor 2)−0.9±1.0−1.1±1.0−0.8±1.2nsns
Direct Effects of Nicotine Scale (DENS); difference score (postsmoking minus presmoking)‡
 Dizzy18.9±25.022.9±27.8 8.7±15.2 nsP<0.10
 Lightheaded26.6±25.630.3±28.1 10.2±19.2 nsP<0.05
 Excess salivation3.6±11.86.2±14.07.8±16.4nsns
 Heart pounding8.5±19.613.2±19.97.0±13.9nsns
Direct Effects of Tobacco Scale (DETS); postsmoking score‡
 Satisfying59.2±22.362.5±23.4 47.0±25.8 nsP<0.10
 Pleasant61.8±18.161.0±25.3 47.4±24.1 nsP<0.01
 Taste good61.2±24.463.9±24.552.7±25.6nsns
 Taste bad16.9±17.115.2±17.722.3±22.1nsns
 Calm40.9±25.1 47.2±26.6 33.8±25.6P<0.10ns
 Awake25.4±21.9 32.0±25.3 23.0±22.4P<0.10ns
 Reduce hunger18.8±17.8 27.2±25.1 23.3±21.2P<0.05ns
 Sick14.1±17.7 20.4±17.9 11.5±15.1P<0.10ns
 Sleepy28.9±25.629.3±27.3 16.6±20.1 nsP<0.01
 Like to smoke another WP right now14.9±18.714.6±19.116.8±22.1nsns
  • *Statistical comparisons were made between control and each configuration. Bolded entry indicates significant difference from control at a p value of 0.10 or smaller. The p values were adjusted for multiple testing.

  • †Responses from one participant were not collected.

  • ‡MNWS, DENS and DETS are VAS ranging from 0 to 100 (not at all to extremely); QSU-brief is Likert scale ranging from 1 to 7 (strongly disagree to strongly agree).

  • §One participant had a missing value in QSU (post item #3) for control, so when creating a mean value for factor 1 the mean was substituted for the missing value.

  • DETS items were rated postsmoking only. Both control and bubble diffuser use charcoal heating of the tobacco, whereas electric uses electric heating. Except for the DETS, scores used for analysis were difference scores (postsmoking minus presmoking).

  • ns, not significant; VAS, visual analogue scales.