Adherence to Timely Vaccinations in the United States.

OBJECTIVES: To estimate (1) the proportion of children not adhering to the Advisory Committee on Immunization Practices (ACIP) recommended early childhood immunization schedule and (2) associations between schedule adherence, sociodemographic characteristics, and up-to-date immunization status by 19 to 35 months of age. METHODS: We used 2014 National Immunization Survey provider-verified vaccination data to classify vaccination patterns as "recommended" (ie, in line with ACIP dose- and age-specific recommendations), "alternate" (ie, in line with either limiting the number of shots per visit or skipping at least 1 vaccine series), or "unknown or unclassifiable" (ie, not in line with ACIP recommendations or clearly limiting shots per visit or vaccine series). We evaluated the association between vaccination patterns and up-to-date status for all ACIP-recommended vaccinations (including rotavirus and hepatitis A vaccines) using Poisson regression. RESULTS: The majority of children's patterns were classified as "recommended" (63%), with 23% and 14% following alternate or unknown or unclassifiable patterns, respectively; 58% of children were up-to-date with all ACIP-recommended immunizations by 19 to 35 months. Not being up-to-date was associated with alternate (prevalence ratio = 4.2, 95% confidence interval: 3.9-4.5) and unknown or unclassifiable (prevalence ratio = 2.4, 95% confidence interval: 2.2-2.7) patterns. CONCLUSIONS: High vaccine coverage by 19 to 35 months of age may miss nonadherence to the recommended immunization schedule in the first 18 months of life, leaving children vulnerable to preventable diseases. With more than one-third of US children not following the ACIP schedule, targeted interventions are needed to minimize vaccine delays and disease susceptibility.

Development of a US trust measure to assess and monitor parental confidence in the vaccine system.

OBJECTIVE: To develop a Vaccine Confidence Index (VCI) that is capable of detecting variations in parental confidence towards childhood immunizations centered on trust and concern issues that impact vaccine confidence. METHODS: We used a web-based national poll of 893 parents of children <7 years in 2016 to assess the measures created for the Emory VCI (EVCI). EVCI measures were developed using constructs related to vaccine confidence identified by the U.S. National Vaccine Advisory Committee (i.e., "Information Environment", "Trust", "Healthcare Provider", "Attitudes and Beliefs", and "Social Norms"). Reliability for EVCI was assessed using Cronbach's alpha. Using the variables related to each of the constructs, we calculated an overall EVCI score that was then assessed against self-reported childhood vaccine receipt using chi-square and the Cochrane-Armitage trend tests. RESULTS: Respondents' EVCI scores could range from 0 to 24, and the full range of values was observed in this sample (Mean = 17.5 (SD 4.8)). EVCI scores were significantly different (p ≤ 0.006 for all comparisons) between parents who indicated their child(ren) received routinely recommended vaccines compared with parents who indicated they had delayed or declined recommended immunizations. There was also a significant, consistent association between higher EVCI scores and greater reported vaccine receipt. CONCLUSIONS: We developed EVCI to reliably measure parental vaccine confidence, with individuals' scores linked to parental vaccine-related attitudes, intentions, and behaviors. As such, EVCI may be a useful tool for future monitoring of both population and individual confidence in childhood immunization.

Development of a measure to assess vaccine confidence among men who have sex with men.

BACKGROUND: Recent serogroup C meningococcal disease outbreaks led to meningococcal vaccine recommendations for Southern California men who have sex with men (MSM). Assessment of vaccine confidence is critical to improving vaccine coverage in the context of disease outbreaks wherein immunization(s) are recommended. METHODS: We surveyed MSM using venue-based sampling and began development of the vaccine confidence index (VCI) with 30 survey items corresponding to trust- and safety-related perceptions. We performed exploratory factor analyses and computed the Cronbach's alpha coefficient to assess internal consistency of the VCI. We created a categorical confidence variable (low, medium, and high confidence) and conducted bivariate and multivariate analyses to evaluate associations with reported confidence and immunization uptake. RESULTS: Ten survey items were included in the final VCI and formed the confidence measure. Participants with low confidence had the lowest levels of reported uptake for both meningococcal vaccines. Confidence differed significantly (p ≤ 0.05) between MSM who indicated they received vaccines recommended within the context of the outbreak and those who did not. CONCLUSIONS: Our VCI is sensitive to a number of issues that may influence vaccine confidence. It is useful for assessing MSM trust and acceptance of recommended immunizations and may be used to inform intervention development.

Collecting outcome data of a text messaging smoking cessation intervention with in-program text assessments: How reliable are the results?

BACKGROUND: Text messaging interventions have shown promise in helping people quit smoking. Texting programs periodically survey participants about their smoking status. This study examined the consistency of participant self-reported smoking between external surveys and internal program text message assessments. METHODS: Participants in Text2Quit program were surveyed about their past 7-day smoking at one, three, and six months post-enrollment using different survey modes (external surveys and internal program text message assessments) and responses were compared for consistency. The first set of analyses was conducted for participants responding on both modes (n = 45 at one month; n = 50 at three months; n = 42 at six months). Additional analyses, assuming missing = smoking, were conducted with the full sample of 262 smokers (68.7% female, mean age = 35.8 years) and compared to saliva-confirmed abstinence rates. RESULTS: Participants responding to both modes consistently reported smoking status at one (88.9%), three (88.0%) and six (88.1%) months post-enrollment, with fair to substantial levels of agreement (one month: κ = 0.24; three months: κ = 0.63; six months: κ = 0.66). Participants responding to both modes reported high rates of abstinence. In missing = smoking analyses, significant differences in abstinence rates reported across modes were detected at each timepoint (one month: external = 30.5%, internal = 16.4%; three months: external = 33.2%, internal = 16.0%; six months: external = 31.7%, internal = 12.2%; all p < .001). Moderate levels of agreement were found between the two modes. At 6 months, abstinence rates obtained via internal data were closer to those biochemically verified (15.7%) compared to external surveys. CONCLUSIONS: Results provide initial support for the use of internal program assessments in text messaging programs with missing = smoking assumptions in order to gather outcome data on smoking behavior.

A randomized trial of Text2Quit: a text messaging program for smoking cessation.

BACKGROUND: Text messaging programs on mobile phones have shown some promise in helping people quit smoking. Text2Quit is an automated, personalized, interactive mobile health program that sends text messages to offer advice, support, and reminders about quitting smoking. PURPOSE: To evaluate the effect of Text2Quit on biochemically confirmed repeated point prevalence abstinence in the context of an RCT conducted in the U.S. METHODS: Participants (n=503) were recruited on the Internet and randomized to receive Text2Quit or self-help material. Between 2011 and 2013, participants were surveyed at baseline and at 1, 3, and 6 months post-enrollment to assess smoking status. Saliva was collected from participants who reported not smoking in the past 7 days at the 6-month follow-up. An intent to treat analysis was used, and those lost to follow-up were categorized as smokers. All analyses were completed in 2013. RESULTS: Biochemically confirmed repeated point prevalence abstinence favored the intervention group, with 11.1% abstinent compared to 5.0% of the control group (relative risk=2.22, 95% CI=1.16, 4.26, p<0.05). Similarly, self-reported repeated point prevalence abstinence was higher in the intervention group (19.9%) than in the control group (10.0%) (p<0.01). Effects were found to be uniform across the analyzed demographic subgroups, although suggestive of a larger effect for non-whites than whites. CONCLUSIONS: These results provide initial support for the relative efficacy of the Text2Quit program.