Peter Cummings

Systemic Corticosteroids in Infant Bronchiolitis: A Meta-analysis

Objective. To determine whether corticosteroids are efficacious in treating bronchiolitis in hospitalized infants. Methods. Online bibliographic databases (Medline, Embase, and Cochrane Clinical Trials Registry) were searched for: 1) bronchiolitis or respiratory syncytial virus, and 2) corticosteroid or glucocorticoid or steroidal antiinflammatory agents or adrenal cortex hormones. Reference lists from all selected articles were also examined. Randomized, placebo-controlled trials of systemic corticosteroids in treatment of infants hospitalized with bronchiolitis were selected by 2 investigators. Of 12 relevant publications identified in the literature search, 6 met the selection criteria and had relevant data available. Investigators independently extracted data for 3 outcomes: length of stay (LOS), duration of symptoms (DOS), and clinical scores. Results. In the pooled analysis, infants who received corticosteroids had a mean LOS or DOS that was .43 days less than those who received the placebo treatment (95% confidence interval: −.81 to −.05 days). The effect size for mean clinical score was −1.60 (95% confidence interval: −1.92 to −1.28), favoring treatment. Secondary analyses of mean LOS or DOS were performed on 5 trials that had clearly identified methods of randomization, 5 trials that measured LOS, and 4 trials that clearly excluded infants with previous wheezing. The estimates of effect were similar to the primary analysis but were not statistically significant. Conclusions. Combined, published reports of the effect of systemic corticosteroids on the course of bronchiolitis suggest a statistically significant improvement in clinical symptoms, LOS, and DOS.

The Relative Merits of Risk Ratios and Odds Ratios

When a study outcome is rare in all strata used for an analysis, the odds ratio estimate of causal effects will approximate the risk ratio; therefore, odds ratios from most case-control studies can be interpreted as risk ratios. However, if a study outcome is common, the odds ratio will be further from 1 than the risk ratio. There is debate regarding the merits of risk ratios compared with odds ratios for the analysis of trials and cohort and cross-sectional studies with common outcomes. Odds ratios are conveniently symmetrical with regard to the outcome definition; the odds ratio for outcome Y is the inverse of the odds ratio for the outcome not Y. Risk ratios lack this symmetry, so it may be necessary to present 1 risk ratio for outcome Y and another for outcome not Y. Risk ratios, but not odds ratios, have a mathematical property called collapsibility; this means that the size of the risk ratio will not change if adjustment is made for a variable that is not a confounder. Because of collapsibility, the risk ratio, assuming no confounding, has a useful interpretation as the ratio change in average risk due to exposure among the exposed. Because odds ratios are not collapsible, they usually lack any interpretation either as the change in average odds or the average change in odds (the average odds ratio).

Characteristics of drowning by different age groups.

Context: While it is known that the risk of unintentional drowning varies with age, the manner in which drowning episode characteristics vary by age has not been well described. Such information might be useful for prevention. Objective: To describe characteristics of drowning by age group. Design: Retrospective review of the characteristics of drowning victims and their drowning incidents obtained from death certificates, medical examiner, pre-hospital, emergency department, and hospital records. Setting: Three counties in Western Washington state. Subjects: Residents who died (n=709) of unintentional drowning within the study region during 1980 through 1995. Outcomes: Age specific counts, proportions, and rates per million person years were estimated for and compared among six age groups. Results: Rates varied by age group: 0–4 (30.5), 5–14 (11.6), 15–19 (29.9), 20–34 (21.5), 35–64 (12.5), and 65 years or older (21.2). Among those 0–4 years, the proportions that drowned in pools, bathtubs, and open water were nearly equal. But from age 5–64 years, over 69% of deaths were in open water. Among those 65 years and older, the deaths were almost evenly divided between bathtub and open water; bathtub drowning rates were highest in this age group, 10.9. Pre-drowning activities were divided into boating, swimming, car passenger, bathing, and fell in while doing something else. Most (64/89, 76%) victims aged 0–4 years drowned while bathing or after falling in. Among those 15–19 years, most occurred while swimming (24/79, 34%) or boating (22/79, 31%). The drowning event was least often witnessed among those 0–4 years (10/36, 28%), and most often witnessed (44/58, 76%) among those 15–19 years. Medical care (pre-hospital, emergency department, or hospital) was most often involved in drownings of those 0–4 years (70/89, 79%) and least among those over 65 years (11/86, 13%). Conclusion: The characteristics of drowning episodes vary greatly by age. Different prevention strategies may be needed for different age groups.

Antibiotics to prevent infection in pateints with dog bite wounds: A meta-analysis of randomized trials

STUDY OBJECTIVES To determine whether prophylactic antibiotics prevent infection in patients with dog bite wounds. DESIGN Meta-analysis of published studies. METHODS A literature search was performed to identify published, randomized trials of prophylactic antibiotics for dog bite wounds. The relative risk for infection in treated patients compared with controls was used as the measure of effect, and a summary relative risk was calculated. RESULTS Eight randomized trials were identified. The estimated cumulative incidence of infection in controls was 16%. The relative risk for infection in patients given antibiotics compared with controls was 0.56 (95% confidence interval, 0.38 to 0.82). About 14 patients must be treated to prevent one infection. CONCLUSION Prophylactic antibiotics reduce the incidence of infection in patients with dog bite wounds. The full costs and benefits of antibiotics in this situation are not known. It may be reasonable to limit prophylactic antibiotics to patients with wounds that are at high risk for infection.

Identified spouse abuse as a risk factor for child abuse

CONTEXT There are limited data on the extent to which spouse abuse in a family is a risk factor for child abuse. OBJECTIVE To estimate the subsequent relative risk of child abuse in families with a report of spouse abuse compared with other families. DESIGN Cohort study. SETTING Analysis of a centralized US Army database PARTICIPANTS Married couples with children with at least one spouse on active duty in the US Army during 1989-95. MAIN OUTCOME MEASURES The US Army Family Advocacy Programs Central Database was used to identify child and spouse abuse. The exposure was an episode of identified spouse abuse and the main outcome was a substantiated episode of subsequent child abuse. RESULTS During the study period of an estimated 2,019,949 person years, 14,270 incident child abuse cases were substantiated. Families with an incident case of spouse abuse identified during the study period were twice as likely to have a substantiated report of child abuse compaired with other military families, rate ratio, 2.0, (95% confidence interval [CI] 1.9-2.1). Young parental age had the highest rate ratio, 4.9 (95% CI 4.5-5.3) in the subgroup analysis controlling for rank. Identified spouse abuse was associated with physical abuse of a child, rate ratio 2.4 (95% CI 2.2-2.5), and with sexual abuse of a child, rate ratio 1.5 (95% CI 1.3-1.7). Identified spouse abuse was not associated with child neglect or maltreatment, rate ratio, 1.0 95% CI 0.9-1.1) CONCLUSION An identified episode of spouse abuse in a family appears to be associated with an increased risk of subsequent child abuse and serves as an independent risk factor. Therefore. care providers should consider the potential risk to children when dealing with spouse abuse.

Effectiveness of Educational Materials Designed to Change Knowledge and Behaviors Regarding Crying and Shaken-Baby Syndrome in Mothers of Newborns: A Randomized, Controlled Trial

BACKGROUND. Infant crying is an important precipitant for shaken-infant syndrome. OBJECTIVE. To determine if parent education materials (The Period of PURPLE Crying [PURPLE]) change maternal knowledge and behavior relevant to infant shaking. METHODS. This study was a randomized, controlled trial conducted in prenatal classes, maternity wards, and pediatric practices. There were 1374 mothers of newborns randomly assigned to the PURPLE intervention and 1364 mothers to the control group. Primary outcomes were measured by telephone 2 months after delivery. These included 2 knowledge scales about crying and the dangers of shaking; 3 scales about behavioral responses to crying generally and to unsoothable crying, and caregiver self-talk in response to unsoothable crying; and 3 questions concerning the behaviors of sharing of information with others about crying, walking away if frustrated, and the dangers of shaking. RESULTS. The mean infant crying knowledge score was greater in the intervention group (69.5) compared with controls (63.3). Mean shaking knowledge was greater for intervention subjects (84.8) compared with controls (83.5). For reported maternal behavioral responses to crying generally, responses to unsoothable crying, and for self-talk responses, mean scores for intervention mothers were similar to those for controls. For the behaviors of information sharing, more intervention mothers reported sharing information about walking away if frustrated and the dangers of shaking, but there was little difference in sharing information about infant crying. Intervention mothers also reported increased infant distress. CONCLUSIONS. Use of the PURPLE education materials seem to lead to higher scores in knowledge about early infant crying and the dangers of shaking, and in sharing of information behaviors considered to be important for the prevention of shaking.

Effectiveness of primary and secondary enforced seat belt laws

OBJECTIVE The objective of this study was to determine the relative efficacy of primary and secondary enforced motor vehicle occupant restraint laws on the outcomes of restraint use, crash-related mortality, and crash-related injuries. SEARCH STRATEGY We used the Cochrane Collaboration search strategy to search the following electronic databases: MEDLINE, EMBASE, National Technical Information Service (NTIS), Psyc-INFO, ERIC, Nursing and Allied Health (CINAHL), Transportation Research Information Service (TRIS), and EI Compendex. The reference lists from each potentially eligible study were checked, and knowledgeable people in the field were contacted, for additional leads to published reports. SELECTION CRITERIA Studies had to include a comparison of primary enforcement law to no law, secondary enforcement law to no law, or a primary to a secondary law. Any study design was acceptable. Acceptable outcome measures included observed restraint use, and counts or rates of deaths or serious injuries. DATA COLLECTION Data were collected using a standard abstract reporting from. Relative differences in outcomes and absolute differences were calculated when possible. MAIN RESULTS We identified 48 studies for the review. When places or time periods with primary enforcement laws were compared to those without such laws, the relative prevalence of seat belt use ranged from 1.5 to 4.5; the prevalence differences ranged from 10 to 50 per 100 observed drivers. Secondary laws had smaller effects. Two studies evaluated a change in law from secondary to primary enforcement; this was associated with an increase in belt use 6 months later of 5.3 per 100 observed drivers in Louisiana and 18 per 100 drivers in California. Primary enforcement laws were associated with a relative risk of death in MV crashes of .54 to .97. The reduction in mortality associated with secondary enforcement laws was much more modest, with relative risks estimates of .81 to 1.025. Primary enforcement laws were associated with a relative risk of severe injuries of .20 to .89; the association of secondary enforcement laws with severe injuries was smaller. CONCLUSIONS Our review of existing studies suggests that primary enforcement laws are likely to be more effective than secondary laws. However, few studies are of good quality, and quantitative estimates of the relative effect of primary compared with secondary laws are limited.

Injuries of the Head, Face, and Neck in Relation to Ski Helmet Use

Background: The extent to which helmet use reduces the risk of injury in ski- and snowboard-related accidents is unclear. We studied the association of helmet use with injuries of the head, face, and neck among skiers and snowboarders involved in falls and collisions. Methods: We conducted a case-control study, using ski patrol injury reports for the years 2000–2005 from 3 ski resorts in the western United States. We identified all skiers and snowboarders involved in falls or collisions who received care from the ski patrol. Helmet use among persons with injuries of the head (n = 2537), face (n = 1122), or neck (n = 565) was compared with helmet use among those involved in falls and collisions who received care for injuries below the neck (n = 17,674). We calculated odds ratios for head, face, and neck injury among helmeted compared with unhelmeted persons. Results: The adjusted odds ratios were 0.85 for head injury (95% confidence interval = 0.76–0.95), 0.93 for facial injury (0.79–1.09), and 0.91 for neck injury (0.72–1.14). Conclusions: Helmets may provide some protection from head injury among skiers and snowboarders involved in falls or collisions.

Accuracy of external cause of injury codes reported in Washington State hospital discharge records

Objective—To evaluate the accuracy of external cause of injury codes (E codes) reported in computerized hospital discharge records. Methods—All civilian hospitals in Washington State submit computerized data for each hospital discharge to a file maintained by the Department of Health. In 1996, 32 hospitals accounted for 80% of the injury related discharges in this file; from these hospitals, we sampled 1260 computerized records for injured patients in a stratified, but random, manner. An expert coder then visited the 32 study hospitals, reviewed the medical records that corresponded to each computerized record, and assigned an E code for that hospitalization. The computerized E code information was compared with codes provided by the expert reviewer. Results—The incidence of hospitalization for injury based upon computerized hospital discharge data was very similar to that based upon chart review: incidence rate ratio 1.0 (95% confidence interval 1.00 to 1.02). Computerized hospital discharge data correctly ranked injuries in regard to both mechanism and intent. Overall agreement on coding was 87% for mechanism of injury, 95% for intent of injury, and 66% for the complete E code. The sensitivity of computerized hospital discharge data for identification of falls, motor vehicle traffic injuries, poisonings, and firearm injuries was 91% or better. The predictive value positive of coding for these four categories of injury ranged from 88% for motor vehicle traffic injuries to 94% for poisonings. The amount of agreement for intent coding ranged from 84% for firearm injuries to 99% for falls. Agreement on coding of the complete E code ranged from 57% for firearm injuries to 72% for poisonings. Conclusions—Computerized hospital discharge data can be used with confidence to determine how many injuries are treated in a hospital setting and the relative magnitude of various categories of injury. E codes reported in hospital discharge data are a reliable source of information on the mechanism and intent of injury, the two types of information most often used for injury related analyses and priority setting. The detail codes (complete E codes) reported in hospital discharge codes are less reliable and must be used with caution.

Injuries Due to Firearms in Three Cities

BACKGROUND To describe the incidence and outcome of injuries due to firearms, we conducted a population-based study of fatal and nonfatal gunshot wounds in three cities: Memphis, Tennessee; Seattle; and Galveston, Texas. METHODS Records of the police, medical examiners, ambulance crews, and hospital emergency departments and hospital admissions were monitored to identify all injuries caused by firearms that were severe enough to prompt emergency medical treatment. These records were linked to generate a complete picture of each event. Census data were used to calculate rates of injury for various population groups. RESULTS A total of 1915 cases of injury due to firearms were identified between November 16, 1992, and May 15, 1994. The crude rate of firearm injury per 100,000 person-years was 222.6 in Memphis, 143.6 in Galveston, and 54.1 in Seattle. Approximately 88 percent of the injuries were incurred during confirmed or probable assaults; 7 percent were sustained in the course of suicide or attempted suicide; unintentional injuries accounted for 4 percent of the cases. Handguns were used in 88 percent of the cases in which the type of weapon was recorded. Five percent of the 1677 victims who were brought to a hospital emergency department could not be resuscitated; 53 percent were hospitalized, and 42 percent were treated and released. Ninety-seven percent of the deaths occurred within 24 hours of the injury. Emergency department and inpatient charges exceeded