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J K MacDonald

Publications and source records attributed to J K MacDonald.

29 records · Page 2Linked to original sources

Infection control in the orthodontic office in Canada.

Because of the difficulty of identifying infected persons, current recommendations for infection control are to treat all patients as if they are infected with blood-borne pathogens such as human immunodeficiency virus (HIV) and the hepatitis viruses. Dentists' compliance with these recommendations has been investigated previously, however, there are few data related to orthodontists. The objective of this study was to measure the proportion of orthodontists who report the use of recommended infection control procedures and to compare the infection control practices of orthodontists and general dentists. A mailed survey with three follow-up attempts was administered to all orthodontists and general dentists in Ontario (N = 5441) in 1994. There were significant differences in the routine use of gloves (orthodontists 85%, general dentists 92%); masks (orthodontists 38%, general dentists 75%); protective eyewear (orthodontists 60%, general dentists 84%); changing gloves after each patient (orthodontists 84%, general dentists 96%); and heat sterilization of handpieces (orthodontists 57%, general dentists 84%). Hepatitis B virus (HBV) vaccination of all clinical staff was reported by 46% of orthodontists, compared with 61% of general dentists (p < 0.001). Reports of HBV vaccination of orthodontists (94%) and general dentists (92%) were not significantly different. The use of additional precautions for patients with HIV was reported by 80% of orthodontists and 78% of general dentists. More education is required to promote the use of universal precautions by both general practitioners and orthodontists. Increased use of barrier methods, HBV vaccination of clinical staff, and heat sterilization of handpieces is required to reduce the potential for cross infection in the orthodontic practice. This is particularly important with the increasing number of microorganisms that are resistant to antibiotics.

Acquired Immunodeficiency Syndrome↗

The infection control practices of general dental practitioners.

OBJECTIVES: To investigate the infection control practices of general dentists in Ontario in 1994. DESIGN: Confidential coded questionnaires were mailed to all general dental practitioners in Ontario (n = 5,176), with three follow-up attempts. Data were analyzed using Pearson's chi-squared test and multiple logistic regression. SETTING: Offices of general dental practitioners in Ontario. PARTICIPANTS: General dental practitioners actively involved in treating patients. RESULTS: The response rate adjusted for nondelivery was 70%. A high proportion of respondents reported using gloves (always, 91.8%; sometimes, 7.8%), masks (always, 74.8%; sometimes, 21.1%), or protective eyewear (always, 83.6%; sometimes, 13%); heat sterilization of handpieces (83.9%); and hepatitis B (HBV) vaccination of dentists (92.3%). However, only 61.4% of respondents reported HBV vaccination of all clinical staff, and 87.7% used additional precautions for patients with human immunodeficiency virus (HIV). Significant predictors of the use of recommended infection control procedures (i.e., always using gloves, masks, and eye protection; heat sterilization of handpieces; HBV vaccination for dentist and staff; and no extra precautions for patients with HIV) were age < 40 years (odds ratio [OR], 2.6), lack of concern regarding increased personal risk (OR, 2.0) or costs of infection control procedures (OR, 1.5), and knowledge of the low infectivity of HIV after a needlestick injury (OR, 2.0) and that infection control procedures for HBV are adequate for HIV (OR, 2.7). CONCLUSION: Additional education is required to promote a more realistic perception of risk of HIV transmission in the dental office and the use of all recommended infection control practices, including Universal Precautions.

Adult↗

Nonresponse bias in a national study of dentists' infection control practices and attitudes related to HIV.

The aim was to investigate late response and nonresponse bias in a survey related to HIV and infection control. Questionnaires with ID numbers were mailed to a stratified random sample of dentists in Canada with additional mailings 4 and 7 weeks later (n = 6444). We compared responses received after < 4 weeks, 4-7 weeks, > 7 weeks. Extrapolation was used to estimate nonresponse bias. Univariate analyses showed significant differences between responses received < 4 weeks after initial mailing and those received later for items on sociodemographics, knowledge, infection control practices and attitudes: late responders were more likely to report that they would refuse to treat any patients with HIV (P < 0.01). Multiple logistic regression indicated that the best predictors of responses received > or = 4 weeks were disagreement that HBV is more infectious than HIV (OR = 1.7); unwillingness to attend a dentist who treats HIV/AIDS patients (OR = 1.3); incorrect perception of the risk of HIV infection after an HIV-contaminated needlestick injury (OR = 1.2); and sometimes or never heat-sterilizing handpieces after each patient (OR = 1.2). Extrapolation indicated that the percentage of all respondents who reported refusal to treat (15.2%) would have been 17.1% if a 100% response rate had been obtained. We found significant evidence of late response and nonresponse bias primarily in knowledge and fears related to HIV infectivity; however, the impact on the final results was small and we concluded that additional follow-up to improve response rates would not be worthwhile.

Acquired Immunodeficiency Syndrome↗

Nonresponse bias in a survey of Ontario dentists' infection control and attitudes concerning HIV.

OBJECTIVE: This study investigated late response and nonresponse bias in an HIV-related survey of dentists. METHODS: Questionnaires with ID numbers were mailed to all dentists in Ontario (N = 5,997) with additional mailings four and seven weeks later. RESULTS: Proportionately more respondents who returned questionnaires less than four weeks after the first mailing reported that they knowingly treated (P < .05) or were willing to treat HIV-infected patients (P < .05); that they had an accurate perception of risk of HIV infection after a needlestick injury (P < .01), and preferred not to refer HIV-infected patients (P < .01). Linear extrapolation of cumulative percent responses indicated nonresponse bias in terms of attitude and knowledge items; however, the magnitude was low. CONCLUSIONS: The effects of late response and nonresponse bias on the results of this study were small. However, these results cannot be generalized beyond the study population, and obtaining high response rates and testing for nonresponse bias in surveys of attitudes related to HIV are recommended.

Acquired Immunodeficiency Syndrome↗

Illnesses and absence due to illness among children attending child care facilities in Seattle-King County, Washington.

OBJECTIVES: Although much of the economic impact of child care-associated illness in the United States is due to parents' time lost from work, there are no data on the incidence of absence due to illness among children in various types of out-of-home child care settings in the United States. The goals of this study were to compare the incidence of illness and absence due to illness among children attending child care homes (CCHs) and child care centers (CCCs). METHODS: From July 1992 through June 1993, child care providers from 91 CCHs and 41 CCCs in Seattle-King County, Washington, provided information on absenteeism and illness for 96 792 child-weeks of observation. RESULTS: The age-adjusted incidence of provider-reported illness episodes among children in CCHs (10.4 episodes per 100 child-weeks) was greater than that among children in CCCs (6.7 episodes per 100 child-weeks). The incidence density ratio of illness among children <1 year of age in comparison to those >/=5 years of age in CCCs (4.5) was greater than that among similar groups in CCHs (2.3). The age-adjusted incidence of absence due to illness among children in CCHs (5.1 days per 100 child-weeks) was less than that among children in CCCs (8.9 days per 100 child-weeks). CONCLUSIONS: Results comparing the incidence of illness between children in various types of child care settings may be influenced by information sources. The incidence of illness among children in CCHs may be greater than that among children in CCCs. The increased incidence of absence due to illness among children in CCCs compared with that among children in CCHs probably reflects differences in exclusion and attendance policies and practices between these two types of settings.

Absenteeism↗

Active and passive surveillance for communicable diseases in child care facilities, Seattle-King County, Washington.

OBJECTIVES: The purpose of this study was to develop and evaluate models for public health surveillance of illnesses among children in out-of-home child care facilities. METHODS: Between July 1992 and March 1994, 200 Seattle-King County child care facilities participated in active or enhanced passive surveillance, or both. Reporting was based on easily recognized signs, symptoms, and sentinel events. Published criteria were used in evaluating surveillance effectiveness, and notifiable disease reporting of participating and nonparticipating facilities was compared. RESULTS: Neither surveillance model was well accepted by child care providers. Enhanced passive and active surveillance had comparable sensitivity. Reporting delays and the large amount of time needed for data entry led to problems with timeliness, especially in terms of written reporting during active surveillance. CONCLUSIONS: Widespread active public health surveillance in child care facilities is not feasible for most local health departments. Improvements in public health surveillance in child care settings will depend on acceptability to providers.

Administrative Personnel↗

Gender differences in characteristics, infection control practices, knowledge and attitudes related to HIV among Ontario dentists.

We surveyed 5,997 dentists in Ontario to investigate gender differences in the characteristics, infection control practices, knowledge and attitudes regarding the treatment of HIV-infected patients. The response rate was 70.3%. Reports indicated that female dentists are younger and more likely to work in larger urban centres (P < 0.00001), and in general practice (P < 0.0001) than their male counterparts. Multiple logistic regression analyses indicated that many significant gender differences in the univariate analyses could be explained by the confounding influence of age, practice location, and specialty; however, some differences remain significant: Women were more likely than men to report attending continuing education dealing with HIV/AIDS in the past two years (P < 0.001), and to use masks and eye protection (P < 0.00001). Men reported more economic concerns than women: they were more concerned about the financial burden of infection control costs (P < 0.00001), and losing patients from their practice if it is known that they treat patients with HIV (P < 0.05). However, there were no significant differences in willingness to provide treatment for patients with HIV. We conclude that there is little evidence to show that access to oral care for patients with HIV is affected by gender differences.

Acquired Immunodeficiency Syndrome↗

Injuries and their relation to potential hazards in child day care.

OBJECTIVES: To prospectively determine the incidence rate of injuries that required medical attention among children in day care and to identify possible hazards related to these injuries. SETTING: King County, Washington. METHODS: Prospective cohort study of children in a sample of licensed day care facilities. RESULTS: From 1 July 1992 to 30 June 1993, 53 medically attended injuries were reported by 133 day care sites; incidence rate 1.9 per 100,000 hours of day care attendance. The rate of injury in 91 small family day care homes was essentially the same as that in 42 larger day care centers; relative rate 1.0 (95% confidence interval 0.6 to 1.9). Injuries that required sutures accounted for 39% of the cases, while 17% required a cast, splint, or sling. No child was hospitalized. Sixty nine sites were inspected and all had potentially correctable physical hazards, with a median of 15 hazards per site (range 7 to 26). These potential hazards had little relationship to the risk of injury and a case-by-case review identified only two injuries that might have been prevented by a more energy absorbent playground surface. CONCLUSIONS: The incidence of medically attended injuries found in this study is consistent with other studies from the United States. Most injuries were minor and had little relation to physical hazards at day care locations.

Accident Prevention↗

Quitting smoking: why, how, and what might help.

OBJECTIVE: To examine reasons for quitting smoking, methods used in quitting, reasons for continuing smoking and potential aids to quitting in the population of Ontario, Canada. DESIGN: Two population-based, telephone interview surveys, conducted by random-digit dialing. SUBJECTS: Adults aged 18 years of age and older in 1983 (n = 1383) and 1991 (n = 1421). MAIN OUTCOME MEASURES: Information was obtained from former smokers on why and how they quit smoking, and from continuing smokers on why they smoked and what might help them quit. RESULTS: The proportion of current smokers in the population decreased from 35.5% in 1983 to 27.2% in 1991. In both surveys, former smokers cited a variety of reasons for quitting, including personal health concerns, social and environmental factors, personal attitude factors, cost, and health education messages. Responses concerning the most important reason also revealed a range of factors; "advice of a physician" was not prominent among them. When questioned about methods used in quitting, most former smokers in both surveys responded that they "just decided to quit". Very few reported using other aids such as cessation clinics or nicotine gum. More smokers in 1991 than in 1983 reported that they continued smoking for enjoyment, to satisfy a craving or addiction, and for relaxation. With regard to what might help them quit, continuing smokers in both surveys cited a wide variety of potential aids, including information on harmful effects, more restrictions on smoking and on sales, cessation clinics, programmes on radio/TV, and higher taxes. CONCLUSIONS: These findings support a multifaceted approach to tobacco control.

Health Promotion↗

Syrinx extending from conus medullaris to basal ganglia: a clinical, radiological, and pathological correlation.

A 41-year-old woman with a history of birth injury to the brachial plexus suffered several delayed episodes of neurological deterioration. Magnetic resonance imaging studies revealed a syrinx extending from the conus medullaris into the brainstem and rostrally into both internal capsules. She died of an acute exacerbation of chronic respiratory failure. Autopsy demonstrated syringomyelia and syringobulbia with cavity extension bilaterally along the corticospinal tracts into the internal capsules. Islands of glial tissue in the subarachnoid space around the medulla caused obstruction of the subarachnoid space at the foramen magnum. These were probably the result of birth injury to the cerebellum. A detailed clinico-pathological correlation is provided to explain her neurological deficits. The pathogenesis of syrinx formation is discussed in terms of a late manifestation of birth trauma.

Adult↗

Geographic differences in the attitudes, knowledge and infection control practices of Ontario dentists.

Geographic differences in the HIV related attitudes, knowledge and behaviours of 5,997 dentists in Ontario were investigated using mailed questionnaires (response rate 70%). Proportionately more respondents from larger population centres reported that they knowingly treated HIV-infected patients (p < 0.00001), they were unwilling to treat HIV-infected patients (p < 0.05), they had an exaggerated perception of the risk of HIV infection after a needlestick injury (p < 0.01), they were concerned about personal risk (p < 0.01) and staff fears (p < 0.05) related to HIV/AIDS, and that patients with HIV or AIDS should be treated in hospitals/specialized practices (p < 0.001). Multiple logistic regression analysis controlling for age, sex, and specialty, showed that respondents who practised in smaller population centres were significantly more willing to treat HIV-infected patients ( < 10,000, odds ratio = 1.6; 10,000-49,999, odds ratio = 1.3). Significantly fewer respondents in the Central West, and Central East Health Planning Region, where AIDS is most prevalent, reported that they were willing to treat HIV patients.

Adult↗