Description of respondents and vaccination rates
Weighted percentages indicated that approximately two-thirds of respondents were females and 50–64 years old; less than one-half had more than a high school education; most had low to modest income levels and approximately half of the participants were black (Table
1). One third rated their health as fair or poor, while most visited their doctors three or more times per year, were nonsmokers, regularly used seat belts and took dietary supplements such as vitamin and mineral supplements. Only 45% reported ever receiving pneumococcal vaccine. In the subset of individuals for whom medical record review was available, the overall pneumococcal vaccination rate was 55.1%. When self-reported vaccination was compared with medical records, there was a high degree of correlation with sensitivity of 0.80, specificity of 0.82, positive predictive value of 0.84, negative predictive value of 0.77 and kappa of 0.61 (
P < 0.001).
Table 1
Descriptive characteristics of the sample (n = 375).
Site | | |
Health Center A | 48 | 200 |
Health Center B | 52 | 175 |
Demographics
|
Age | | |
50–64 | 64 | 185 |
≥65 | 36 | 190 |
Gender | | |
Female | 63 | 241 |
Male | 37 | 134 |
Race | | |
African American | 47 | 172 |
Caucasian | 53 | 187 |
Marital Status | | |
Married | 31 | 114 |
Single | 14 | 46 |
Widowed | 26 | 113 |
Separated/divorced | 30 | 100 |
Education Level | | |
Elementary/some high school (grades 1 to < 12) | 22 | 93 |
High school graduate/vocational or technical school | 39 | 144 |
Some college/college graduate | 27 | 95 |
Graduate/professional school | 12 | 42 |
Household Income | | |
<$10,000 | 33 | 117 |
$10,000 – 19,999 | 30 | 104 |
$20,000 – 39,999 | 18 | 59 |
$40,000 or more | 19 | 62 |
Employment Status | | |
Unemployed | 61 | 252 |
Employed part- or full-time | 39 | 121 |
Health Behaviors
|
Self-rated health | | |
Excellent/Very good | 38 | 143 |
Good | 31 | 120 |
Fair/poor | 31 | 110 |
Physician visit frequency | | |
Every 1–2 months | 25 | 96 |
3–4 times/year | 36 | 137 |
Less than 2 times/year | 39 | 139 |
Time since last complete physical exam | | |
< 1 year | 73 | 273 |
1–2 years | 16 | 59 |
> 2 years | 11 | 36 |
Smoking status | | |
Current smoker | 27 | 93 |
Never a smoker | 31 | 119 |
Former smoker | 42 | 163 |
Frequency of seatbelt use | | |
Always | 67 | 253 |
Sometimes | 23 | 83 |
Never | 10 | 34 |
Use of dietary supplements | | |
Yes | 63 | 236 |
No | 37 | 139 |
Received 2001–02 influenza vaccine | | |
Yes | 53 | 210 |
No | 47 | 161 |
Ever received pneumococcal vaccine | | |
Yes | 45 | 183 |
No | 55 | 179 |
Although black participants reported lower educational and income levels, lower self-rated health and fewer were employed, they visited their physicians more frequently, had had a more recent complete physical exam and were more often smokers. Notably, there were no differences overall between blacks (49%) and whites (42%) in pneumococcal immunization status by self-report (P = 0.215).
Recommendations for pneumococcal vaccination differ for those older or younger than 65 years; therefore, all subsequent analyses were stratified by age group. Self-reported pneumococcal vaccination rates were 69% for those 65 years and older and 32% for those 50–64 years.
Among the 50–64 year old group, those who were unemployed, visited the doctor more frequently, had a more recent complete physical exam, self rated their health lower and received the 2001–02 influenza vaccine, were significantly more likely than their respective counterparts, to have ever received the pneumococcal vaccine (P < 0.05). Likewise, a positive attitude toward the pneumococcal vaccine and having had the vaccine recommended by their physician, or relatives or friends was associated with significantly higher pneumococcal vaccination rates (P < 0.001). Racial differences in pneumococcal vaccination rates among younger patients (39% for blacks vs. 26% for whites; P = 0.061) were not significant.
Among those 65 years and over, being a woman, being a nonsmoker, taking dietary supplements, having a more recent complete physical exam, and having received the 2001–02 influenza vaccine were all significantly associated with higher pneumococcal vaccination rates (
P < 0.05). As in the younger group, a positive attitude toward pneumococcal vaccine and having received a recommendation to get the pneumococcal vaccine were significantly associated with higher pneumococcal vaccination rates (
P < 0.001). There were no significant differences in pneumococcal vaccination rates by race in this age group either (67% for blacks vs. 70% for whites;
P = 0.624). In logistic regression analyses (Table
2), two factors increased the likelihood of receiving pneumococcal vaccine in the 50–64 year-old group: seeing a physician more frequently and receiving the 2001–02 influenza vaccine. Among adults 65 years and older, females, as well as those who had received the 2001–02 influenza vaccine, were more likely to have received the pneumococcal vaccine.
Table 2
Determinants* of receipt of pneumococcal polysaccharide vaccine by age group.
Female (referent, male) | | | 3.79 (1.47 – 9.74) | .006 |
Received the influenza vaccine in 2001–02 | 5.78 (2.51 – 13.30) | <.001 | 12.88 (5.36 – 30.95) | <.001 |
Last physical was < 1 year ago | 2.82 (1.08 – 7.36) | .034 | | |
Frequency of visits to physician (referent, <1 per year) | | | | |
6–12 times per year | 3.39 (1.12 – 10.29) | .031 | | |
3–4 times per year | 1.82 (0.69 – 4.81) | .229 | | |
Because receipt of influenza vaccine was so highly related to receipt of pneumococcal vaccine, we wished to examine the relationship between various factors and receipt of both influenza and pneumococcal vaccines, compared with receipt of neither vaccine. Bivariate analyses by age group indicated that receipt of both vaccines among patients 50–64 years was significantly associated with being unemployed, having health insurance, fair or poor self-reported health, more recent complete physical exam and more frequent visits to the physician (P < 0.005). For the older group, having better self-rated health, being a nonsmoker, having health insurance, more recent complete physical exam and having seen posters advertising flu shot clinics were associated with receiving both vaccines (P < 0.05). In bivariate analyses, most Triandis model factors were similarly associated with receipt of both vaccines as they were to receipt of pneumococcal vaccine alone, for both age groups.
Table
3 shows significant factors related to receiving both pneumococcal vaccine and the most recent influenza vaccine compared with having received neither using logistic regression. For patients 50–64 years, being employed was associated with a lower odds ratio of being vaccinated, while more frequent visits to the physician and belief that a person who does not get the flu shot will probably get the flu were associated with higher likelihood of being vaccinated against pneumococcus and receiving the most recent influenza vaccine. For patients 65 years old and older, being a nonsmoker, having seen posters advertising flu shot clinics, believing that a person who does not get the flu shot will probably get the flu, and having family or friends who feel that the patient should get the flu shot were positively associated with receiving both vaccines.
Table 3
Determinants* of receiving pneumococcal polysaccharide vaccine ever and most recent influenza vaccine (n = 145) compared with having received neither vaccine (n = 121)
Employed part- or full-time (referent, unemployed) | .33 (.11 – .96) | .042 | | |
Frequency of visits to physician (referent, <1 per year) | | | | |
6–12 times per year | 4.40 (1.09 – 17.78) | .038 | | |
3–4 times per year | 8.77 (2.36 – 32.62) | .001 | | |
Smoking status (referent, current smoker) | | | | |
Never smoked | | | 10.67 (1.67 – 68.28) | .012 |
Quit smoking | | | 7.51 (1.38 – 40.84) | .020 |
Saw posters for flu shot clinic | | | 5.85 (1.60 – 21.37) | .008 |
Believes that a person who does not get the flu shot will probably get the flu | 4.67 (1.61 – 13.54) | .005 | 3.98 (1.01 – 15.71) | .048 |
My family/friends think I should get the flu shot | | | 10.28 (2.85 – 37.00) | .001 |