The Conduct of Practice-Based Research in Community Clinics Compared to Private Practices: Similarities, Differences, and Challenges

As a result of this initiative, in 2005 the National Institute of Dental and Craniofacial Research (NIDCR) awarded three 7-year grants to establish dental practice-based research networks (PBRNs)³ . One of the funded networks was the Northwest Practice-based REsearch Collaborative in Evidence-based DENTistry (PRECEDENT), ⁴ administered by the schools of dentistry at the University of Washington in Seattle and the Oregon Health and Science University (OHSU) in Portland. The other two networks are the Dental Practice-Based Research Network (DPBRN)⁵ and the Practitioners Engaged in Applied Research and Learning (PEARL) Network.⁶ Through the grant period, each network is expected to complete a substantial number of studies comparing the benefits of different dental procedures, dental materials, and prevention strategies "under a range of patient and clinical conditions."³

In response to this NIDCR request, the Northwest PRECEDENT network actively recruited and developed studies to include general dentists not only those who were in private practice but also those providing care to underserved populations through clinics in community health centers. It would be expected that underserved patients and their dental healthcare providers have different oral healthcare and research needs, respectively, compared with patients and dentists in the private practice setting. In addition, the outcomes and challenges associated with engaging in practice-based research could be expected to differ between the two practice settings. This article aims to document, describe, and contrast the similarities and unique challenges related to conducting research in community clinics compared with private general dentistry practices within the Northwest PRECEDENT network. Although the Northwest PRECEDENT now includes orthodontists and pediatric dentists as members, this article is limited to general dentists. This comparison of the conduct of practice-based research performed in community clinic versus private practice settings benefits from the rather unique perspective of this article's primary author, who has participated in Northwest PRECEDENT studies in both practice settings.

Study Design and Selection of Practices and Patients
Information was obtained from meetings with Northwest PRECEDENT dentist investigators and two cross-sectional studies. Since 2006, four Northwest PRECEDENT annual meetings for all dentist investigators and one specific meeting for community clinic dentist-investigators occurred. Dentists had the opportunity to express their research interests and share their research experience with colleagues and the Northwest PRECEDENT staff.

General dentists who volunteered for the Northwest PRECEDENT practice-based research network completed online surveys. A total of 22 community clinic general dentists and 231 private practice general dentists completed their surveys from April 2005 to July 2009.

A survey of oral health conditions of the patients and the treatments received in the dental practices was performed as Study 1 in the Northwest PRECEDENT network from September 2006 to July 2009. All general dentists in the network who had completed all required training were invited to participate. Patients were selected using a systematic randomized sample of dental visits. Dental offices were compensated for their participation in the study based on estimates of time required by the staff and dentists to complete the study. Detailed methodological information is reported elsewhere, ⁷ including data on the entire study sample of 101 dentists and 1943 patients. A total of 1903 patients were enrolled from four community clinics and 95 private practices and are reported here. The study protocol, including the consent process, was reviewed and approved by the OHSU Institutional Review Board.

Data Collection
Information on the similarities and differences between community health clinics and private practices in the conduct of research was obtained through narratives of the participating practitioner investigators during the meetings and the authors' experiences with conducting the research in community health clinics and private practice. In addition, the experience of the study's research coordinators in training the dental offices on conducting several studies also contributed to the narrative.

Dentists completed online questionnaires about themselves and their practices. Information collected included dentist's age, sex, race/ethnicity, and number of years practicing dentistry; the community setting (rural/suburban/urban); practice arrangement (private group or solo practice, managed care, community clinic, or other); practice location (Idaho, Montana, Oregon, Utah, or Washington); and the numbers of dentists in the practice, days of practice, and patients seen per week. The data reported here are only from the community clinics and private solo or group practices.

Data on diagnosis and treatment of several oral conditions were collected through clinical examinations and dental chart reviews. During the clinical examinations, patients were asked about age, sex, race/ethnicity, use of orthodontic appliances or occlusal splints, and the reason for the current visit. During the chart reviews, information on number of teeth and the diagnosis of dental caries, pulpitis, gingivitis, periodontal disease, and orofacial pain in the last 12 months were collected. Data on dental prophylaxis, preventive, restorative, and endodontic treatments performed in the last 12 months were also obtained through the chart reviews.

Statistical Analysis
The distribution of the sociodemographic characteristics of dentists and patients, the oral health conditions of the patients, and the treatments provided in the past 12 months were examined by practice type, using descriptive statistics. To take into account the clustering of patients within practices, 95% confidence intervals were calculated using the Taylor series linearization method from the PROC SURVEYFREQ procedure. Chi-square and Fisher exact tests were used to test for differences between community clinic and private practice dentists. Design-adjusted chi-square tests were used to examine differences between community and private practice patients (tests were not presented for fewer than five observations per cell). Analyses were performed using SAS 9.2 for Windows® software (SAS Institute Inc, https://www.sas.com).

Similarities between community clinics and private practices
Similarities and differences between community clinics and private practices are summarized in Figure 1. In relation to the similarities in practice organization, both community and private practices are primarily focused on the clinical treatment of patients, so time for research activities is limited. The commitment of time resources to conduct research was moderate; on average, dentists completed the survey of 20 patients in 2.5 months (standard deviation = 2.9).

The training of the dentists and staff were among the similarities in research requirements for community clinics and private practices. Both community clinic dentists and private practice dentists were required to complete a course on the principles of good clinical research, ⁸ as well as online training on responsible conduct of research in humans and a review of relevant Health Insurance Portability and Accountability Act (HIPAA) regulations for research. Dentists and staff also participated in training for study-specific methods and Web-based data entries.

Other research requirements similar in community and private practices were the processes of informing the patient population about the involvement of the dental office in the research project, obtaining informed consent, and collecting data for the study.

Additional similarities for the conduct of practice-based research in community and private practices were administrative requirements to develop and maintain processes for the secure storage of research records and to have a reliable connection to the Internet for data transmission.

Differences between community clinics and private practices
As indicated in Figure 1 , one of the key differences between community clinics and private practices that affect the conduct of practice-based research is the nature of the patient populations seeking care and their treatment needs. In the Study 1 patient survey, most patients included (1839) were seen in private practices. However, contrasting them with the 64 seen in community clinics, as in Table 1, documents the actual observation of the kinds of differences one might expect.

Statistically significant differences between the patient samples included age, sex, race/ethnicity, and prevalence of dental caries and periodontal bone loss. In the patient population from the community clinics, 50% were younger than 18 years, 12.5% were older than 45 years, 60.9% were females, and 60.7% were from races/ethnicities other than non-Hispanic white. Non-English speaking patients were also more common in community clinics, and many patients could not be enrolled in the study due to difficulties in reading and understanding the consent forms. In contrast, in the patient population of the private practices, 12.9% were younger than 18 years, 53.3% were older than 45 years, 55.1% were females, and 14.4% were from races/ethnicities other than non-Hispanic white. Seventy-five percent of community clinic patients had dental caries in the previous year, while 54.6% of private practice patients had dental caries in the previous year ( P <.001). The prevalence of periodontal disease was 16.7% among community clinic patients and 36% among private practice patients ( P =.01). The prevalence of orofacial pain was 21% for community clinic patients and 14.5% among private practice patients ( P =.06) (Table 1).

As shown in Table 2, there were statistically significant differences between community and private practice patients for treatment needs, including oral health maintenance and restorative treatment as the reason for the current visit and preventive and restorative treatments performed in the previous 12 months. Forty-one percent of the community clinic patients were visiting the general dentist for oral health maintenance and 37.5% for restorative dentistry, while 52.6% of the private practice patients were visiting for maintenance and 26.3% for restorative dentistry ( P =.01). Among the treatments performed in the previous 12 months, 72.1% of the community clinic patients received one or more preventive treatments (fluoride varnish, topical application of fluorides, and sealants) compared with 31.8% of private practice patients ( P <.01). Thirty-six percent of the community clinics versus 10.2% of private practice patients received at least one amalgam restoration ( P <.001) and 20.3% of the community clinic patients compared with 35.1% of private practice patients received at least one composite restoration (Table 2).

In addition, the practice organizations differed with respect to patient volume. As shown in Table 3, A total of 73% of the community clinic dentists reported having more than 50 patient visits per week, on average; whereas, 53.1% of the private practice dentists had 50 or more patient visits per week ( P =.08).

Differences between community clinics and private practices in the way research was conducted included patient selection, participant follow-up, and research interests. In the private practices, patients were invited to participate in the study during the telephone call confirming the appointment. Community clinics experience a high number of unscheduled visits, so the opportunity to contact in advance a patient to be seen in a randomly selected appointment time significantly decreased. Instead, patients were informed about their selection to participate in the study as they presented to the clinic. Due to these differences, inclusion criteria for Study 1 differed slightly between the two settings in that most private practices preferred to not enroll new patients into the study, while community clinics enrolled both patients of record and new patients.

The research interests of community clinic dentists were also different than those of dentists in private practice. During meetings when study topics were discussed and ranked according to levels of importance and interest, community clinic dentists expressed most interest in topics related to deep caries and caries prevention, including behavioral changes, while private practice dentists expressed greater interest in topics, such as cracked teeth, endodontics, crown and bridge restorations, and implants.

Community clinic dentists were younger than private practice dentists (31.8% vs 67.1% were older than 40 years; P =.002) and worked with other dentists in the same clinic (86.4%) while 74% of private practice dentists practiced solo ( P <.001) (Table 3).

The conduct of dental practice-based research in both private practice and community clinic settings can have many similarities, differences, and challenges. Research conducted in the community clinic setting can have its own unique challenges related to the burden of disease, limited resources, external locus of control, increased fluctuations in scheduling, and the often transient nature of the population served.

At the same time, practice-based research conducted in private practices and community clinics have many similarities. Practitioners faced multiple competing needs within their busy practices, and time commitment appeared to be the most significant obstacle regardless of the practice setting. Time challenges presented in many forms, including the initial research certification of dentists and their designated staff, the patient chair time required to complete the study, and the dedication of a staff member to complete data entry. Practitioner-investigators were also challenged with managing processes both familiar and foreign to the clinical practice of dentistry. Practices were required to have a reliable connection to the Internet for data transmission and to develop and maintain processes for informed consent, tracking of study participants, record maintenance, and security.

Practitioner-investigators caring for the underserved in the community clinic setting encountered unique barriers to participating in practice-based research. Some community clinic patients have cultural traditions and customs, language barriers, and different oral health needs, which can hinder treatment efforts. In the patient survey reported here, the community clinic patients were younger and experienced more acute diseases, such as dental caries, than private practice patients did. They also visited the dentist for different reasons, had more preventive treatments and amalgam restorative treatments, and sought fewer routine dental check-ups. Treatment of acute dental needs is prolific in community clinics, resulting in approximately 1 million emergency services and dental extractions nationwide in 2007.⁹ Furthermore, in order to maintain federal grant funding status as an organization providing care to underserved populations, community clinic dentists must sustain a level of productivity set by the Health Resources Service Administration.¹⁰ In light of this almost insurmountable burden of disease and justifiable requirement of productivity, participating in "extracurricular" activities such as practice-based research that take the clinician away from direct patient care may simply be out of reach for many community clinic dentists.

Interconnected with this situation is community clinic staffing. Many community clinics have chronic understaffing of dentists and/or auxiliary staff.¹¹ Paramount to the concept of practice-based research is the involvement of the entire dental team, including the dentist and possibly just as importantly the support staff. Community clinics that hold vacancies for numerous months may experience a severe patient backlog, which, in turn, increases the point-in-time demand for services, thereby again constricting the "extracurricular" time available to community clinic dentists. With larger staffs and more than one dentist in the clinics, it is harder to have a research team that works together with good division of duties. In addition, some community clinics may find it challenging to acquire additional funding for the competitive compensation packages needed to attract staff to support even the most basic functions, such as delivering patient care, let alone supporting practice-based research.

Unlike private practices, the locus of control for practice policies, rules, and overall goals does not remain with the practicing dentists in community clinics. All community clinics have a governing board of directors and executive director.¹² Ultimately, the community clinic dentist must acquire approval from these entities before commencing any research. Community clinic dentists desiring to conduct practice-based research are required to "build a persuasive case" before the board of directors and executive director. Most community clinic administrators strongly desire their clinicians to remain professionally satisfied and to further health improvement in their populations of focus. If resources are even marginally adequate, governing boards and executive directors are likely to allow community clinic dentists to participate in practice-based research.

When a governing body has approved participation in practice-based research, many challenges await the community clinic dentist. First, identifying randomly selected study participants (when called for) with the high number of unscheduled visits is a challenge. Second, there is the difficult task of tracking this more mobile population for study follow-up. A higher loss of participants compared to research conducted in the private practice setting is anticipated. Finally, there is the challenge of keeping a community clinic practitioner-investigator engaged. The research interests of these practitioners are different than those dentists in private practice, and m any community clinic sites have both medical and dental facilities on site. As an outgrowth of this understanding, the Northwest PRECEDENT developed a subgroup within the network consisting of community clinic dentists. This community clinic subgroup provides an opportunity to identify and help design studies of particular interest in their setting.

Limitations of the studies reported here include the limited number of community clinic dentists who participated in the survey of the oral health conditions of their patients and the treatments provided in their dental practice. Only four community clinic dentists had completed the required trainings on principles and responsible conduct of research during the patient survey study period and concentrated efforts to invite more community clinic dentists to the Northwest PRECEDENT network were performed after this period. For this reason, in this part of the study, only 64 patient participants were from community clinics; the comparisons of the patient characteristics and treatment needs between community and private practice patients should be interpreted with caution. Nevertheless, the sampling process provided what is likely to be samples as representative of care-seeking patients in the two settings as is possible, given the limitations of sampling within busy practices. Therefore, it is noteworthy that significant differences were identified between the two settings that confirmed and documented what was anticipated based on conventional wisdom. Community clinic patients and their dental healthcare providers have different research needs and challenges from their counterparts in private practice. Practice-based research networks can be successfully implemented in both settings; however, proper support and acknowledgment of the variations and unique barriers in community clinics are needed for success in that setting.

The authors would like to thank the invaluable contributions of the dentist-investigator members of the Northwest Practice-based REsearch Collaborative in Evidence-based DENTistry (Northwest PRECEDENT) and their staff. Submitted on behalf of the Northwest PRECEDENT network, with support from National Institute of Dental Craniofacial Research grants DE016750 and DE016752.

The authors encourage all practitioners who are interested in learning more about the research network and how to participate to visit https://www.nwprecedent.net.

Jane Gillette, DDS
Northwest PRECEDENT Dentist-Investigator
Private Practice
Mint Dental Studio
Bozeman, Montana

Joana Cunha-Cruz, DDS, PhD
Research Assistant Professor
Dental Public Health Sciences
University of Washington
Seattle, Washington

Ann Gilbert, BS
Research Coordinator
Northwest PRECEDENT
University of Washington
Seattle, Washington

Pollene Speed-McIntyre, DDS
Acting Assistant Professor
Department of Restorative Dentistry
University of Washington
Seattle, Washington

Northwest PRECEDENT Dentist-Investigator
Private Practice
Seattle, Washington

Lingmei Zhou, MS
Research Consultant
Dental Public Health Sciences
University of Washington
Seattle, Washington

Timothy DeRouen, PhD
Professor
Department of Dental Public Health Sciences/Department of Biostatistics

Executive Associate Dean
University of Washington
Seattle, Washington