Background
Prior approaches to reducing SHS exposure among the very young
Challenges related to parental perceptions and practices
Third hand smoke exposure
Primary hypothesis of the current study
Specific aims
Methods/Design
Project Phases
Phase
|
Activity
|
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I. Program development | |
Systematic review of the professional literature (with meta-analysis) | |
Comprehensive search for intervention materials available online, | |
Consultation with experts | |
Creation of initial version of website | |
Development of research instruments (questionnaires and Interview Guides | |
Focus groups and in-depth interviews with parents about attitudes and practices regarding child tobacco smoke exposure Qualitative evaluation | |
Focus groups with parents on measurement of exposure Qualitative evaluation | |
Design workshops to get feedback from parents on all elements of program. Qualitative evaluation | |
II. Pilot
| Pilot all elements of intervention and research materials on 5-10 groups of 10 parents each. Qualitative and quantitative evaluation |
III. Cluster randomized RCT
| Randomize 18 clinics to early or late intervention, with 30 participants per clinic. Quantitative evaluation of primary and secondary endpoints, qualitative and quantitative process evaluation. |
Phase I. Intervention Development
Phase II: Pilot of developed intervention
Phase III. Cluster randomized controlled trial
Population
Intervention
General Focus
Intervention Components
Outcome Measures
List of Outcome Measures
Measurement
Measurement of TSE
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Hair nicotine levels. Hair will be cut at the scalp prior to and 3-6 months after the intervention. Several centimeters of several hairs will be taken from hair at the scalp. The proximal 1 cm of hair represents exposure during the previous month.
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Parental report of child TSE, obtained through questionnaires, including information on frequency of regular exposure, smoking habits of both parents, smoking bans in house and car, smoking behavior of frequent and occasional visitors; exposure to regular smoking elsewhere (such as in daycare or at grandparent).
Justification of choice of TSE measures
Statistical Considerations
Statistical analysis
Sample size calculation for the Phase III trial
Sample size formula
Specification of the effect size
Estimation of the Inflation Factor (IF)
Estimation of the standard deviation (SD)
Hair Nicotine
Published N | Published Geometric Mean | Published Confidence Interval | SD for Log Hair Nicotine | |
---|---|---|---|---|
No exposure | 101 | 0.58 | [0.49,0.68] | 0.84 |
Smoke outside the house | 69 | 2.63 | [2.03,3.40] | 1.09 |
Smoke inside the house | 127 | 5.62 | [4.60,6.86] | 1.15 |
Hair Cotinine
Calculated Sample Size
Log Hair Nicotine | Log Hair Cotinine | |
---|---|---|
R = 0.25 | 880 | 1,160 |
R = 0.33 | 450 | 600 |
R = 0.50 | 150 | 200 |