Assessment of quality of life among patients with sinonasal disease as determined by an Internet survey based on the Rhinosinusitis Disability Index.

Abstract

We conducted a survey to measure patient quality of life with the Rhinosinusitis Disability Index adapted for the Internet. Our target population was patients who were seeking information on sinonasal disease on the World Wide Web. Usable responses were obtained from 896 patients with self-diagnosed sinonasal disease. According to the survey responses, patients with chronic rhinosinusitis were significantly more bothered by their condition than were patients with allergic rhinitis. Also, women were significantly more impaired by recurrent acute sinusitis and chronic rhinosinusitis than were men. Our findings are consistent with the results of previous surveys conducted by means other than the Internet. This project represents the first quality-of-life survey of an unsolicited group of individuals with sinonasal disease. We believe that use of the Internet will allow

researchers to obtain larger patient populations than is now typical with traditional means of survey dissemination.

Introduction

Nasal and sinus diseases have a substantial impact on patient quality of life, and their treatment requires the expenditure of large amounts of healthcare resources. In 2005, for example, rhinosinusitis affected more than 29 million adult Americans. (1) In 1996, overall healthcare expenditures attributable to sinusitis were estimated at $5.8 billion?

The prevalence of sinonasal disease and the number of dollars spent on treating it make this entity a relevant topic for research on quality of life. Well-known quality-of-life assessment tools, such as the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36), are based on standard survey techniques. However, these surveys are sometimes difficult to administer or are poorly received by the population being surveyed. Moreover, health surveys can be hard to interpret because of difficulties in identifying an appropriate sample population and in generating an acceptable response rate. As a general rule, confidence in the interpretation of survey results increases in direct proportion to the number of usable responses obtained. Although the prevalence of sinonasal disease makes it an ideal subject for a quality-of-life survey, a given investigator may still encounter trouble identifying a sufficient number of patients, even in an academic setting or single-specialty group practice with a large patient volume.

A relatively new way of recruiting patients for surveys is the use of the World Wide Web. In this article, we describe the results of our Internet-based study, in which we used an Internet version of the Rhinosinusitis Disability Index (RSDI) to survey an unsolicited group of subjects with a self-reported diagnosis of allergic rhinitis, recurrent acute sinusitis, or chronic rhinosinusitis.

Patients and methods

The RSDI is a validated 30-question survey tool. (3) It is used to measure the impact of sinonasal disease on a patient's overall quality of life, as well as on three subsets: functional, emotional, and physical health states.

For our study, the RSDI was adapted for Internet use by a Web-design firm, and the survey was posted on the Web site of the Sinus and Allergy Health Partnership (SAHP; www.sahp.org). Respondents were asked to identify themselves by age range and sex and to choose one of three diagnoses that they felt best represented their disease process: allergic rhinitis, recurrent acute rhinosinusitis, or chronic rhinosinusitis. Users were provided with descriptions of each disease to assist them in making their choice. For each question, patients had the option of providing one of five answers, each of which was assigned a point value: never (0 points), almost never (1), sometimes (2), almost always (3), and always (4). Lower scores correlated with a better quality of life.

Surveys were completed from Jan. 1,2003, through Oct. 24, 2005. The respondents' data were downloaded on a local computer for analysis. An average score was calculated for each category; the denominator was adjusted to reflect incomplete answers. The two-tailed Student's t test was used to analyze scores by sex, diagnosis, and health-status subset. Results were expressed as adjusted (least squares) means and standard error from an ANOVA model. Statistical significance was defined as p < 0.05.

Results

In all, we received 1,006 survey responses. We rejected those surveys in which the respondent did not indicate his or her sex and those in which 6 or more data elements were not completed. This left us with 896 usable responses--594 (66.3%) from women and 302 (33.7%) from men. Of this group, 211 respondents (23.5%) said they had allergic rhinitis, 418 respondents (46.7%) self-diagnosed chronic rhinosinusitis, and 267 respondents (29.8%) indicated recurrent acute rhinosinusitis.

In general, RSDI scores indicated that women tended to be more negatively affected by their disease than men (table 1). Women with recurrent acute rhinosinusitis had a significantly higher overall score and significantly higher subset scores for functional state and physical state than did men with the same diagnosis. Likewise, women with chronic rhinosinusitis had a significantly higher score for physical state than did men with chronic rhinosinusitis.

Pair-wise comparisons among all respondents regardless of sex indicated that those with chronic rhinosinusitis had significantly higher scores than did the other respondents in almost every parameter measured (table 2). In general, overall RSDI scores indicated that patients with allergic rhinitis were least affected by their disease and patients with chronic rhinosinusitis were most affected by it.

Discussion

The growth of the World Wide Web has made it easy for patients with Internet access to obtain health information. Many thousands of health-related Web sites are available. Sites that are hosted by reputable institutions and organizations provide patients with a high level of confidence in the content. However, many other sites operate with little or no peer-review oversight, and the information they dispense may be incorrect or misleading.

Most health Web sites generally transmit information to patients along a "one-way street." Content providers can make their sites more interactive by placing a survey on the site. This allows for a two-way exchange of information, which should improve a provider's understanding of various disease entities. During our study, the SAHP used its Web site to help patients understand their disease better. Respondents received instant feedback on their scores, and they were told how their scores compared with historical RSDI values reported by Senior et al.4 Another advantage of our use of the SAHP's Web site was that it allowed us to survey six times as many patients as Senior et al did in their initial report of the RSDI (n = 142). (4)

Our results reflected statistically significant differences across a number of measures that were not identified by Senior et al. (4) For example, we found that in some respects, women were significantly more impaired by recurrent acute sinusitis and chronic rhinosinusitis than were men. However, the higher overall scores recorded by the women cannot be explained by the disease process alone because the pathophysiology of rhinosinusitis is the same in the two sexes. It is possible that the differences between the sexes may be attributable to differences in the ways in which men and women use the Internet; women are more likely to use the Internet to obtain health information. Also, patients with more serious disease may be more likely to seek information online.

Our survey represents the first quality-of-life evaluation of an unsolicited group of patients with sinonasal disease. Obviously, a self-diagnosis by an unsolicited, anonymous survey respondent is not as legitimate as an in-person diagnosis by a clinician. The accuracy of self-diagnoses may also be undermined by misinterpretations, mistaken beliefs, wrong conclusions, unsuitability for inclusion in the sample population, and a variety of other factors. Likewise, the reliability of the responses can be distorted by the use of proxy responses (i.e., answers submitted by someone other than the "official" respondent), deliberate untruthfulness, etc. (5) However, we believe that the availability of the diagnostic aids presented on the SAHP Web site and the sophistication of Internet users justifies our confidence in their self-diagnoses.

Our confidence in the reliability of our results is also bolstered by the fact that our findings revealed that chronic rhinosinusitis was a more serious problem than recurrent acute rhinosinusitis, which in turn was more bothersome than allergic rhinitis. Such a finding is not only intuitive, but it also confirms the findings of Senior et al. (4) The fact that our population's responses were in accordance with this pattern, despite all the opportunities for respondent error, supports the validity of our survey results. Also, both the overall scores and the subset scores were nearly identical to those reported by Senior et al (4) and Birch et al, (6) both of whom conducted formal diagnostic evaluations based on well-accepted criteria. We do not know how many of our respondents based their answers on an actual diagnosis by a clinician and how many had not been formally diagnosed but, again, our results were consistent with those cited in previously published reports. (4,6)

Internet-based surveys have several advantages over traditional methods of data collection: (1) they are not subject to interviewer bias, (2) they provide anonymity for respondents, which may lead to more honest responding, (3) they provide a suitable platform for asking complex questions, (4) they are relatively inexpensive, (5) data can be collected and compiled rapidly, and (6) data are less vulnerable to processing and coding errors. (5,7)

Based on our experience and in view of the high prevalence of sinonasal disease, the high degree of disability associated with it, and the high cost of treating it, we believe that the RSDI may be a good initial tool for patients to assess not only their level of dysfunction, but perhaps their response to treatment, as well. The opportunity to compare their findings with published data may prompt patients to seek care earlier than they otherwise might have, and this should have a beneficial effect on the healthcare system overall.

Acknowledgments

The authors thank Alissa Kapke of the Department of Biostatistics and Research Epidemiology at the Henry Ford Health System for her review and presentation of the data. We also thank the Sinus and Allergy Health Partnership for hosting this survey on its Web site.

References

(1.) Chronic sinusitis. National Center for Health Statistics. Centers for Disease Control and Prevention Web site. www.cdc.gov/nchs/ fastats/sinuses.htm. Last reviewed Feb. 22, 2007. Accessed July 9, 2007.

(2.) Ray NF, Baraniuk JN, Thamer M, et al. Healthcare expenditures for sinusitis in 1996: Contributions of asthma, rhinitis, and other airway disorders. J Allergy Clin Immunol 1999;103(3 Pt 1):408-14.

(3.) Benninger MS, Senior BA. The development of the Rhinosinusitis Disability Index. Arch Otolaryngol Head Neck Surg 1997; 123(11): 1175-9.

(4.) Senior BA, Glaze C, Benninger MS. Use of the Rhinosinusitis Disability Index (RSDI) in rhinologic disease. Am J Rhinol 2001;15(1):15-20.

(5.) Non-sampling error. Statistics Canada. www.statcan.ca/english/ edu/power/ch6/nonsampling/nonsampling.htm. Updated Nov. 8, 2006. Accessed June 19, 2007.

(6.) Birch DS, Saleh HA, Wodehouse T, et al. Assessing the quality of life for patients with chronic rhinosinusitis using the "Rhinosinusitis Disability Index." Rhinology 2001;39(4):191-6.

(7.) SuperSurvey Knowledge Base. Why survey? Tercent, Inc. http:// knowledge-base.supersurvey.com/survey-goals.htm. Updated March 18, 2005. Accessed June 19, 2007.

William C. Kinney MD, MHA; Michael S. Benninger, MD

From the Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia (Dr. Kinney), and the Department of Otolaryngology-Head and Neck Surgery, Henry Ford Hospital, Detroit (Dr. Benninger).

Reprint requests: William C. Kinney, MD, Department of Otolaryngology-Head and Neck Surgery, University of Missouri, One Hospital Dr., MA314, Columbia, MO 65212. Phone: [phone]; fax: [phone]; e-mail: [e-mail]

Table 1. Mean RSDI scores by diagnosis, subset, and sex

                                                   Subset score
                                 Emotional state   Functional state

Diagnosis                           F       M         F        M

Allergic rhinitis   (n = 211)      130     81        130      81
                    Mean score    14.88   16.59     15.82    15.83
                    SD            8.23    8.74      6.47     6.69
Recurrent           (n = 267)      196     71        196      71
acute               Mean score    17.16   15.79     17.55   15.46 *
rhinosinusitis      SD            8.65    9.70      6.49     7.38
Chronic             (n = 418)      268     150       268      150
rhinosinusitis      Mean score    18.53   18.11     18.91    18.07
                    SD            8.42    8.81      6.42     7.06

                                  Physical state

Diagnosis                           F            M

Allergic rhinitis   (n = 211)      130           81
                    Mean score    19.26        17.94
                    SD            7.02          7.06
Recurrent           (n = 267)      196           71
acute               Mean score    21.71   18.63 ([dagger])
rhinosinusitis      SD            7.78          8.70
Chronic             (n = 418)      268          150
rhinosinusitis      Mean score    22.01        19.77
                    SD            7.97          8.45

                                      Total

Diagnosis                           F        M

Allergic rhinitis   (n = 211)      130      81
                    Mean score    49.96    50.36
                    SD            19.84    20.90
Recurrent           (n = 267)      196      71
acute               Mean score    56.42   49.88 *
rhinosinusitis      SD            21.42    24.58
Chronic             (n = 418)      268      150
rhinosinusitis      Mean score    59.45    55.95
                    SD            20.86    22.41

* p < 0.05 for males vs. females (two-sample Student's t test).

([dagger]) p < 0.01 for males vs. females (two-sample Student's t
test).

Key: F =female; M = male; SD = standard deviation.

Table 2. Adjusted (least squares) mean RSDI scores by subset and
diagnosis

                                Adjusted mean score

                          Allergic           Recurrent acute
Subset                    rhinitis           rhinosinusitis

Emotional state    15.52 (0.60)              16.77 (0.55)
Functional state   15.71 (0.46)              16.77 (0.42)
Physical state     18.49 (0.55) ([dagger])   20.37 (0.50)

Total              49.72 (1.49) ([dagger])   53.91 (0.36)

                     Adjusted mean score

                            (SE)
                           Chronic
Subset                 rhinosinusitis

Emotional state    18.36 (0.43) * ([dagger])
Functional state   18.47 (0.33) * ([dagger])
Physical state     20.89 (0.39) *
Total              57.72 (1.07) * ([dagger])

* Significantly different from allergic rhinitis (p < 0.05).

([dagger]) Significantly different from recurrent acute
rhinosinusitis (p < 0.05). Key: SE = standard error.