Which of the following vaccine responses should be reported to the physician immediately?

Pediatrics. Author manuscript; available in PMC 2018 Jul 16.

Published in final edited form as:

PMCID: PMC6046639

NIHMSID: NIHMS980020

Allison Kempe, MD, MPH,a,b Sean T. O’Leary, MD, MPH,a,b Allison Kennedy, MPH,c Lori A. Crane, PhD, MPH,a,d Mandy A. Allison, MD, MPH,a,b Brenda L. Beaty, MSPH,a Laura P. Hurley, MD, MPH,a,e Michaela Brtnikova, PhD,a Andrea Jimenez-Zambrano, MPH,a and Shannon Stokley, MPHc

Abstract

OBJECTIVES

To assess among US physicians (1) frequency of requests to spread out recommended vaccination schedule for children <2 years, (2) attitudes regarding such requests, and (3) strategies used and perceived effectiveness in response to such requests.

METHODS

An e-mail and mail survey of a nationally representative sample of pediatricians and family physicians from June 2012 through October 2012.

RESULTS

The response rate was 66% (534 of 815). In a typical month, 93% reported some parents of children <2 years requested to spread out vaccines; 21% reported ≥10% of parents made this request. Most respondents thought these parents were putting their children at risk for disease (87%) and that it was more painful for children (84%), but if they agreed to requests, it would build trust with families (82%); further, they believed that if they did not agree, families might leave their practice (80%). Forty percent reported this issue had decreased their job satisfaction. Most agreed to spread out vaccines when requested, either often/always (37%) or sometimes (37%); 2% would often/always, 4% would sometimes, and 12% would rarely dismiss families from their practice if they wanted to spread out the primary series. Physicians reported using a variety of strategies in response to requests but did not think they were effective.

CONCLUSIONS

Virtually all providers encounter requests to spread out vaccines in a typical month and, despite concerns, most are agreeing to do so. Providers are using many strategies in response but think few are effective. Evidence-based interventions to increase timely immunization are needed to guide primary care and public health practice.

The current routine childhood immunization schedule is estimated to prevent 42 000 deaths and 20 million cases of disease and to save $14 billion in direct medical costs per US birth cohort.1 Despite these enormous benefits, epidemiologic studies in the United States and internationally have shown that increasing numbers of parents are choosing to delay or refuse certain vaccines because of a variety of concerns.2–6 A recent national survey in the United States demonstrated that 13% of parents of young children reported using some type of alternative vaccination schedule.7 Such alternative schedules can lead to underimmunization, which has been shown to significantly increase the risk of acquiring and transmitting vaccine-preventable diseases.3,8–10

The percentage of parents who refuse all vaccines is a small subset of those who choose alternative schedules overall,7,11 with the majority choosing to delay certain vaccines, extend the interval between vaccines, or delay vaccines until a certain age.12–14 Some parents perceive that alternative schedules that “spread out vaccines” over a longer period of time, with fewer simultaneous injections than the recommended routine schedule may be safer.14–16 There is limited information about how frequently parents are requesting to spread out the childhood vaccine schedule, how these requests are being handled by primary care physicians, and the impact of these requests on primary care practice. This study examines these issues from the perspective of primary care providers nationally, to guide future interventions to increase full and timely childhood immunization. Our objectives were to examine among pediatric and family medicine physicians: (1) their perception of the frequency of parental requests to spread out the recommended schedule for children <2 years and parental reasons for these requests, (2) their attitudes regarding such requests, (3) their responses to these requests, and (4) their perception of the effects of such requests on their practice.

METHODS

We conducted a survey from June to November 2012 among pediatric and family physicians who were part of sentinel networks within each specialty. The human subjects review board at the University of Colorado Denver approved this study.

Study Population

This survey was conducted as part of the Vaccine Policy Collaborative Initiative, a collaboration with the Centers for Disease Control and Prevention to perform rapid turnaround surveys to assess physician attitudes about vaccine issues. We developed national networks of primary care physicians by recruiting from the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP). We conducted quota sampling17 to ensure that network physicians were similar to the AAP and AAFP memberships with respect to region, practice location, and practice setting. Exclusion criteria included practicing <50% primary care, not practicing in the United States, or being in training. We have previously demonstrated that survey responses from network physicians compared with those of physicians randomly sampled from American Medical Association physician databases had similar demographic characteristics, practice attributes, and attitudes about a range of vaccination issues.17

Survey Design

We developed the survey in collaboration with the Centers for Disease Control and Prevention, and with input from the AAP and the AAFP. We used 4-point Likert scales for questions assessing physician attitudes, actions, and assessment of effectiveness of their actions in response to parental requests. A national advisory panel of pediatricians and family physicians pretested the survey. On the basis of their input, respondents were asked about “parents who ‘spread out’ the recommended vaccine schedule due to safety and other concerns,” and spreading out was defined as “postponing 1 or more vaccines with the intent of receiving them later.” The survey was then piloted among 24 pediatricians and 15 family physicians nationally and further modified based on this feedback.

Survey Administration

We surveyed physicians by Internet (Verint, Melville, NY, http://www.verint.com) or, if they preferred, by mail. We sent the Internet group an initial e-mail with up to 8 reminders, and we sent the mail group an initial mailing and up to 2 additional reminders. We sent Internet survey nonrespondents a mail survey in case of problems with e-mail correspondence. We patterned the mail protocol on Dillman’s tailored design method.18

Statistical Analysis

We pooled Internet and mail surveys together for analyses because studies have shown that physician attitudes are similar when obtained by either method.18–20 We compared respondents with nonrespondents using t test and χ2 analyses and compared pediatrician and family physician responses using χ2 and Mantel-Haenszel χ2 tests. We conducted a multivariable analysis with the dependent variable of “often/always” agreeing to spread out vaccines. Independent variables included practice characteristics and strongly agreeing with a variety of attitudes about spreading out vaccines. We used a cutoff of P < .25 for inclusion of demographic variables but only included attitudes associated at <.01 because there were so many with significant associations. Our multivariable models used a backward elimination procedure in which the least significant predictor in the model was eliminated sequentially. At each step, estimates were checked to make sure other variables were not affected by dropping the least significant variable. This resulted in retention of only those factors that were significant at P < .05 in the final model. Analyses were performed by using SAS software, version 9.4 (SAS Institute, Cary, NC).

RESULTS

The overall response rate was 66% (534 of 815), 70% (282 of 405) among pediatricians and 61% (252 of 410) among family physicians. Table 1 compares responders and nonresponders and describes additional characteristics available only for the responders. Among responders, 83 (9 pediatricians and 72 family medicine physicians, 16% overall) indicated that they did not administer vaccines to children <2 years old and were removed from further analysis.

TABLE 1

Comparison of Respondents and Nonrespondents and Additional Characteristics of Respondents’ Practices

Prevalence of Requests to Spread Out Immunizations and Reasons for Requests

Ninety-three percent of physicians reported some parents of children <2 years requested spreading out vaccines in a typical month; 21% reported ≥10% of parents made this request. Compared with the previous year, 23% reported increased, 62% unchanged, and 14% decreased requests. Physicians reported a variety of reasons given by parents requesting to spread out vaccines (Tables 2 and ​3). Almost all reasons given by parents were more commonly reported by pediatricians than family physicians.

TABLE 2

Physicians’ Perceptions of How Much Factors Contribute to Requests to Spread Out the Vaccination Schedule (n = 453)

TABLE 3

Physicians’ Perceptions of How Much Factors Contribute to Requests to Spread Out the Vaccination Schedule by Specialty (N = 453)

Physician Attitudes Regarding Requests

As shown in Fig 1, the vast majority agreed that it was important that all vaccines in the primary series be given on time (92%), that parents who chose to spread out vaccines were putting their children at risk for contracting disease (87%), and that it was more painful for children to bring them back repeatedly for separate injections (84%). The majority also felt that if they agreed to spread out vaccines, it would build trust with families (82%) and that if they did not agree, families might leave their practice (80%). Thirty-five percent thought that if they complied with requests to spread out, they were giving a mixed message to the family, and 40% reported that parental requests to spread out vaccines had decreased their job satisfaction. Compared with family physicians, pediatricians more strongly agreed with most attitudes examined (Fig 1).

Physicians’ attitudes related to spreading out vaccines in primary series (n = 453). *P < .05 for comparison between specialties (χ2 test) when pediatricians strongly agree more than family medicine physicians. *P < .05 for comparison between specialties (χ2 test) when family medicine physicians strongly agree more than pediatricians.

Reported Actions and Strategies Used in Response to Requests

Most physicians reported agreeing to spread out vaccines when requested, either often/always (37%), sometimes (37%), or rarely (26%). Characteristics and attitudes associated with often/always agreeing to spread out in the final multivariable model included pediatric subspecialty, thinking that working with parents regarding the schedule creates a greater degree of trust, and having an understanding of why parents choose to spread out vaccines (see Tables 4 and ​5 for bivariable and multivariable models). Conversely, practicing in an urban inner-city location, thinking it was important that all vaccines be given at recommended times, or feeling that complying with requests to spread out the series would send a mixed message were negatively associated with the outcome. Pediatricians were more likely than family physicians to dismiss families from their practice if they insisted on spreading out vaccines either often/always (3% vs 1%), sometimes (6% vs 1%), or rarely (14% vs 8%; P < .001), respectively.

TABLE 4

Bivariable and Multivariable Models Predicting Agreeing to Spread Out “Often/Always” (N = 438 with nonmissing values)

TABLE 5

Strategies Used and Perceived Effectiveness of Strategies (N = 453)

Table 6 shows strategies used by physicians in response to parental requests to spread out vaccines and their perceived effectiveness in convincing parents to vaccinate their children according to recommended guidelines. Few physicians thought any of the reported responses were “very effective,” although many were thought to be “somewhat effective.”

TABLE 6

Strategies Used and Perceived Effectiveness of Strategies by Specialty (n = 453)

Effects of Requests on Practice

Table 7 shows the reported amount of time providers reported spending personally when discussing vaccines with typical first-time parents of infants or with parents with substantial concerns about vaccines. More pediatricians (57%) than family physicians (34%) reported spending >10 minutes discussing vaccines with parents who have vaccine concerns (P < .001). Pediatricians were also more likely to report that spreading out vaccines created extra work for the practice (54% vs 37% strongly agreed, P < .001). Reported changes in the practice specifically related to requests to spread out vaccines included requiring extra provider visits for administration of vaccines that parents had chosen to defer (29%) and purchasing vaccines with fewer antigens (15%).

TABLE 7

Time Spent Discussing Vaccines With Parents by Specialty (n = 453)

DISCUSSION

In contrast to much of the previous literature regarding parents who refuse all or specific vaccines, the current study focused on the larger group of parents who intend to vaccinate but request to spread out the recommended vaccine schedule. Our data demonstrate that primary care physicians are spending a good deal of time discussing vaccines when parents have concerns, that they are trying a variety of methods of handling requests to spread out the vaccine schedule, and that, in general, they find few methods to be effective in increasing timely vaccination. Although they perceive that there are harms associated with spreading out vaccines, they usually agree to do so.

Data suggest that during the past decade, increasing numbers of parents are choosing to deviate from the recommended vaccine schedule, either using published alternative schedules21–23 or, more frequently, requesting to spread out the recommended schedule without a specific model.4,7 Delaying vaccines has led to more children who are undervaccinated. For example, the prevalence of undervaccination in the first 2 years of life within 8 managed care organizations increased from 41.8% in 2004 to 54.4% in 2008, with ~13% of the total estimated to be undervaccinated by choice.2 Other national surveys have yielded similar percentages of parents who reported requesting some type of alternative schedule.7,12 Our data are difficult to directly compare with these parent surveys because they represent incidence rather than prevalence data and are from the physician’s perspective rather than self-report of parents.

Physicians reported that parents usually discussed their reasons for wanting to spread out vaccines. Reasons given were similar to other published reasons for either deferral or refusal, including concerns about short- and long-term complications, belief that their child is unlikely to get a vaccine-preventable disease, concerns about weakening their child’s immune system, and the belief that the diseases are not severe enough to warrant vaccination.12–14,24 Some commonly reported reasons, however, were more specific to the request to vaccinate on a modified schedule, including a friend or relative’s positive experience with an alternative schedule and the belief that the parents should play a central role in medical decisions about their child. These responses support the importance of social networks in affecting vaccine decisions25 and underline the importance of control over medical decision-making among vaccine hesitant parents.

Many physicians reported tension between the need to build trust with families by being willing to compromise on the schedule while simultaneously feeling they were putting children at risk and causing them unnecessary pain by spreading out vaccines on multiple visits. A sizable portion of physicians, especially pediatricians, reported that this issue was decreasing their job satisfaction. Roughly half of all physicians reported they spend ≥10 minutes in discussions with parents who have substantial vaccine concerns, and among pediatricians, this number was almost 60%. Previous work has shown that both pediatricians and parents26 estimate that well-child visits average ~18 minutes. Therefore, if physician estimates are accurate, they may be spending more than half of their appointment time with families who have vaccine concerns discussing this issue alone. Studies about the content of well-child visits show that although immunizations are virtually always discussed, as available visit time decreases, other issues such as developmental assessment, feeding issues, toilet training, child care, guidance about emotional support, sleep position, car seats, and parental smoking are short-changed.27 A 2006 examination of previous policy statements by the AAP found 162 verbal health advice directives on which pediatricians were recommended to counsel parents and patients throughout childhood.28 When seen in this context, the amount of visit time physicians are spending on vaccine concerns may be compromising their ability to deliver comprehensive preventive care to children of parents with substantial vaccine concerns.

Compared with a 2009 survey conducted in sentinel networks using the same methodology and the same question as in the current study,29 the data reported here show a marked difference in physician responses to parental requests to spread out the vaccine schedule. In 2009, only 13% reported often or always agreeing to spread out vaccines, whereas 37% in the present survey often or always agreed to do so. This shift may reflect changes in the beliefs of physicians about what is effective in working with hesitant parents, adherence to published recommendations about how to build trust with vaccine-hesitant parents, or simply a pragmatic reaction to the amount of time it takes to discuss parents’ concerns in the context of a busy practice setting and, perhaps, the perceived futility of doing so. Our multivariable model suggests that the importance of building trust with parents is a motivator for agreeing to spread out vaccines, but a strongly held belief that agreeing to do so gives parents a mixed message makes physicians less inclined to agree to spread out vaccines.

Pockets of underimmunization have been associated with outbreaks of several vaccine-preventable diseases including pertussis, varicella, pneumococcal disease,9,10,30,31 and, especially in recent years, measles.8,31,32 Additional potential harms of spreading out the vaccine schedule have not been studied. The safety of alternative schedules is unknown, although a recent study demonstrated that delay of the measles, mumps, and rubella vaccine until after 15 months was associated with a higher rate of febrile seizures.33 The psychological effect of bringing children back for single shots at frequent intervals, which most physicians surveyed thought was more painful than receiving immunizations simultaneously, has also not been assessed.

Although physicians report using many strategies in response to requests to deviate from the recommended schedule, they had a relatively bleak perception of the effectiveness of most of them. The strategy most often deemed effective was considered “very effective” by only 20% of physicians. In fact, as pointed out by a recent systematic review, there is virtually no published evidence at present demonstrating effective interventions to persuade parents to vaccinate when they already wish to delay or refuse.34 Most publications have focused exclusively on the interaction between providers and parents and addressed physician communication style, motivational interviewing techniques, or tailoring messages to specific parental positions.35–40 Focusing interventions on this key relationship has been guided by qualitative and survey data from parents in which they cite health care providers as their most trusted source of vaccine information.13,41,42 Indeed, among parent survey respondents who have considered delaying or refusing vaccines, the recommendation of a health provider has been reported as the most common reason for getting vaccines as recommended.12,43

However, it is not clear that providers are having success in changing the minds of parents who come in already requesting to either spread out or refuse vaccines. In a recent study, only 69% of parents who delayed vaccines and 38% of parents who refused vaccines expressed a high level of trust in their pediatrician’s advice on vaccines.44 Despite the educational materials and tools available from national organizations focused45 on how to communicate with hesitant parents and what type of messages to give, almost none have been actually studied in a comparative effectiveness trial to assess the impact of their use. The 1 recent randomized trial to compare different types of messages to increase measles, mumps, and rubella vaccine vaccination found that none increased parental intent to vaccinate and those that attempted to increase concerns about diseases or correct false information about vaccines actually decreased intent to vaccinate among parents who had the least favorable vaccine attitudes.46 Although the messages were delivered over the Internet rather than in a clinical setting by a trusted provider, these results nonetheless underline the importance of testing proposed interventions to see if they actually produce the anticipated effect in real-world settings.

There are important limitations to our findings. Although the sample of sentinel physicians surveyed was designed to be representative of AAP and AAFP memberships, the attitudes, experiences, and practices of sentinel physicians may not be fully generalizable. Additionally, although this survey had a high response rate, nonrespondents may have had different views than respondents. Physicians’ perceptions of why parents are requesting to spread out immunizations may not accurately reflect parents’ viewpoints. Most important, the survey relied on self-report rather than direct observation.

Our study points out the need for an evidence base to guide primary care physicians in efforts to increase timely vaccination. Given the amount of time discussions with vaccine-hesitant parents take, the inability to charge for extra visits focusing solely on such discussions, and competing demands in primary care, interventions that supplement the limited communication that can occur at well-child visits are also needed. Recent data suggest that vaccine discussions need to begin early in pregnancy because that is when vaccine decision-making begins, especially for parents who are hesitant about vaccines, and interventions during this period may be effective.44,47,48 Social marketing methods could be used to target vaccine-hesitant parents who may be considering delaying vaccines before these decisions are made.49 The importance of social networks in shaping parents’ vaccination decisions has been underlined and interventions targeting networks within a community could have broader impact.25 Reinforcing vaccination as a social norm could be better leveraged as it has been in a variety of other health care interventions.50–55 Amplifying the voice of the vast majority of parents who do follow vaccination recommendations in public messaging and in settings such as preschools and schools could be a powerful tool that, up to the present, has not been used on a large scale. Critically, to guide primary care and public health providers, we need to test any of these proposed approaches in real-world settings in comparative effectiveness trials with the outcome of actually increasing timeliness and completeness of vaccinations.

​

WHAT’S KNOWN ON THIS SUBJECT

Some parents choose to “spread out” the recommended vaccine schedule for their child by decreasing the number of simultaneous vaccines or delaying certain vaccines until an older age. Epidemiologic studies demonstrate increasing numbers of parents are choosing to delay vaccines.

WHAT THIS STUDY ADDS

We demonstrate that almost all providers encounter requests to spread out vaccines in a typical month and, despite concerns, increasing numbers are agreeing to do so. Providers report many strategies in response to requests but think few are effective.

Acknowledgments

FUNDING: This investigation was funded by the Centers for Disease Control and Prevention and administered through the Rocky Mountain Prevention Research Center, University of Colorado Anschutz Medical Campus (grant 5U48DP001938).

Biography

• 

Dr Kempe conceptualized and designed the study, contributed to the data collection instrument design, and drafted the initial and final manuscript; Drs O’Leary, Allison, and Hurley and Ms Kenney and Ms Stokley assisted in study design and creation of the data collection instrument and reviewed and revised the manuscript; Dr Crane conceptualized and designed the study, designed the data collection instrument, and reviewed and revised the manuscript; Ms Beaty contributed to the study design, carried out the initial and further analyses, and reviewed and revised the manuscript; Ms Brtnikova and Ms Clinger contributed to the study design and data collection instrument design, coordinated and supervised all data collection, and reviewed and revised the manuscript; and all authors approved the final manuscript as submitted.

Footnotes

This work was presented in part at the annual meeting of the Pediatric Academic Societies; May 4, 2013; Washington, DC.

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.

POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

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