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Peter Cummings

Publications and source records attributed to Peter Cummings.

35 records · Page 2Linked to original sources
PubMed2003

Association of alcohol-related laws with deaths due to motor vehicle and motorcycle crashes in the United States, 1980-1997.

The authors compared US motor vehicle and motorcycle mortality rates during periods when each of several alcohol-related laws were in effect with mortality rates during other periods. During the period 1980-1997, there were 792,184 deaths due to motor vehicle crashes and 63,052 deaths due to motorcycle crashes. An estimated 26% and 49% of these fatalities, respectively, were attributable to alcohol use. The incidence of alcohol-related mortality in motor vehicle crashes was lower when laws specifying a blood alcohol concentration of 0.08 g/dl per se (laws stating that it is a criminal offense to drive with a blood alcohol concentration above the state's legal limit) were in effect (adjusted rate ratio (RR) = 0.86, 95% confidence interval (CI): 0.83, 0.88). For motorcycle deaths, the adjusted rate ratio was 0.87 (95% CI: 0.79, 0.95). The incidence of alcohol-related mortality in motor vehicle crashes was also lower during periods when two other types of laws were in effect: zero tolerance laws (adjusted RR = 0.88, 95% CI: 0.86, 0.90) and administrative license revocation laws (adjusted RR = 0.95, 95% CI: 0.93, 0.98). Overall motorcycle mortality was lower when administrative license revocation laws were in effect (adjusted RR = 0.95, 95% CI: 0.92, 0.98).

Accidents, Traffic↗
PubMed2003

Assessment of volume of hemorrhage and outcome from pelvic fracture.

HYPOTHESIS: Measurement of pelvic hemorrhage on computed tomographic (CT) scans can estimate the pelvic fracture component of total patient blood loss and predict the need for angiography. DESIGN: Retrospective cohort study. SETTING: Large level 1 trauma center. PATIENTS: We examined data from 759 consecutive, nonreferral blunt trauma patients who sustained pelvic fracture. MAIN OUTCOME MEASURES: Pelvic-fracture-specific outcomes included estimation of extraperitoneal pelvic hemorrhage volume from emergency department CT scans and determination of arterial injury from angiograms. General patient outcomes determined from medical record review included transfusion requirement, estimated blood loss, and mortality. Subanalysis was performed on subjects with only pelvic fracture as a source of major hemorrhage (derived from discharge International Classification of Diseases, Ninth Revision, Clinical Modification codes). RESULTS: Overall mortality was 96 (13%) of 759 patients. Blood transfusion was given to 418 (55%) patients, and 258 (34%) received 6 or more units in the first 72 hours. Pelvic-fracture-related hemorrhage averaged 149 mL (range, 0-1423 mL). Angiography was performed on 163 patients, of whom 113 had arterial injury. Higher pelvic hemorrhage volumes on CT scans were seen in subjects with pelvic arterial injury demonstrated on angiograms (P<.001). In subjects without another source of major hemorrhage, pelvic CT hemorrhage volumes were strongly associated with transfusion requirement (P<.001). Subjects with large pelvic hemorrhage volumes (>500 mL) were more likely to have pelvic arterial injury (risk ratio, 4.8; 95% confidence interval, 3.0-7.8; P<.001) and require large-volume (>/=6 U) transfusions (risk ratio, 4.7; 95% confidence interval, 1.8-12.3; P<.001) than patients with smaller pelvic hemorrhage volumes. CONCLUSION: Pelvic hemorrhage volumes derived from pelvic CT scans were predictors of the need for pelvic arteriography and transfusions.

Adolescent↗
PubMed2003

Estimating seat belt effectiveness using matched-pair cohort methods.

Using US data for 1986-1998 fatal crashes, we employed matched-pair analysis methods to estimate that the relative risk of death among belted compared with unbelted occupants was 0.39 (95% confidence interval (CI) 0.37-0.41). This differs from relative risk estimates of about 0.55 in studies that used crash data collected prior to 1986. Using 1975-1998 data, we examined and rejected three theories that might explain the difference between our estimate and older estimates: (1) differences in the analysis methods; (2) changes related to car model year; (3) changes in crash characteristics over time. A fourth theory, that the introduction of seat belt laws would induce some survivors to claim belt use when they were not restrained, could explain part of the difference in our estimate and older estimates; but even in states without seat belt laws, from 1986 through 1998, the relative risk estimate was 0.45 (95% CI 0.39-0.52). All of the difference between our estimate and older estimates could be explained by some misclassification of seat belt use. Relative risk estimates would move away from 1, toward their true value, if misclassification of both the belted and unbelted decreased over time, or if the degree of misclassification remained constant, as the prevalence of belt use increased. We conclude that estimates of seat belt effects based upon data prior to 1986 may be biased toward 1 by misclassification.

Accidents, Traffic↗
PubMed2003

Matched-pair cohort methods in traffic crash research.

Standard analysis of matched-pair cohort data requires information only from pairs in which at least one had the study outcome. This can be useful in traffic fatality studies of characteristics that can vary among vehicle occupants, such as seat belt use, as crash databases often lack information about vehicles in which all survived. However, matching crash victims who were in the same vehicle does not necessarily eliminate confounding by vehicle or crash related factors, because the matched occupants must be in different seat positions. This paper reviews three methods for estimating relative risks in matched-pair crash data. The first, Mantel-Haenszel stratified methods, may produce biased estimates if seat position is associated with the outcome. The second, the double-pair comparison method, was designed to deal with confounding by seat position. If the effects of seat position vary according to some vehicle or crash characteristic which is associated with the study exposure, adjustment for this characteristic may be needed to produce unbiased estimates. Third, conditional Poisson regression and Cox proportional hazards regression can produce unbiased estimates, but may require model interaction terms between seat position and vehicle or crash characteristics. This paper reviews some of the strengths and limitations of each of these methods, and illustrates their use in simulated and real crash data.

Accidents, Traffic↗
PubMed2003

Emergency department analgesia for fracture pain.

STUDY OBJECTIVES: We analyze records of all emergency department (ED) patients with extremity or clavicular fractures to describe analgesic use, compare analgesia between adults and children, and compare analgesia between the subset of these adults and children with documented moderate or severe pain. Among children, we compare treatment between pediatric and nonpediatric facilities. METHODS: Analysis of the ED component of the National Center for Health Statistics National Hospital Ambulatory Medical Care Survey for 1997 through 2000 was conducted. The proportion of patients with closed extremity and clavicular fracture that received any analgesic and narcotic analgesic medications was determined for each age category. Survey-adjusted regression analyses compared pain and narcotic medications by age and ED type (pediatric versus other). Analyses were repeated for the subset of patients with moderate or severe pain severity scores. RESULTS: Of 2,828 patients with isolated closed fractures of the extremities or clavicle, 64% received any analgesic and 42% received a narcotic analgesic. Pain severity scores were recorded for 59% of visits overall, 47% of children younger than 4 years, and 34% of children younger than 1 year. Among patients with documented moderate or severe pain, 73% received an analgesic and 54% received a narcotic analgesic. Compared with adults, a lower proportion of children (< or = 15 years) received either any analgesic or a narcotic analgesic (P <.001). After adjustment for confounders and survey design, the proportion of patients aged 0 to 3, 4 to 8, 9 to 15, 16 to 29, 30 to 69, and 70 years and older who received any analgesic was 54% (95% confidence interval [CI] 41% to 67%), 63% (95% CI 57% to 68%), 60% (95% CI 57% to 64%), 67% (95% CI 62% to 73%), 68% (95% CI 64% to 72%), and 58% (95% CI 52% to 65%), respectively; the proportion who received a narcotic analgesic was 21% (95% CI 11% to 31%), 30% (95% CI 22% to 37%), 27% (95% CI 23% to 32%), 47% (95% CI 40% to 54%), 51% (95% CI 46% to 56%), and 41% (95% CI 35% to 48%), respectively. Compared with children treated in other EDs, children treated in pediatric EDs were about as likely to receive any analgesia (adjusted relative risk [RR] 1.1; 95% CI 0.9 to 1.3) or narcotic analgesia (adjusted RR 0.9; 95% CI 0.6 to 1.2). CONCLUSION: In pediatric and adult patients, pain medications were frequently not part of ED treatment for fractures, even for visits with documented moderate or severe pain. Pain severity scores were often not recorded. Pediatric patients were least likely to receive analgesics, especially narcotics.

Academic Medical Centers↗
PubMed2003

Web-based image review and data acquisition for multiinstitutional research.

OBJECTIVE: In this article, we describe a user-friendly Web-based interface that allows review of images combined with integrated data collection and entry for use at multiple sites involved in a large multicenter research project. CONCLUSION: The Web-based system that we present uses a commercially available Internet browser and Web platform and allows automated data entry that can be easily uploaded into standard data analysis programs. The system simplifies the complex logistics of using multiple sites and reviewers for radiology research and can preserve human subject confidentiality. We tested the system using a large-scale multicenter cohort study of pelvic fracture-related hemorrhage (the "Evaluating Pelvic Hemorrhage" study). Program testing revealed seamless remote image interpretation and data acquisition.

Biomedical Research↗
PubMed2002

Association of helmet use with death in motorcycle crashes: a matched-pair cohort study.

The association of helmet use with death in a motorcycle crash can be estimated using matched-pair cohort methods. By estimating effects among naturally matched pairs on the same motorcycle, one can account for potential confounding by motorcycle characteristics, crash characteristics, and other factors that may influence the outcome. The authors used Fatality Analysis Reporting System data, from 1980 through 1998, for motorcycles that crashed with two riders and either the driver or the passenger, or both, died. For their main analysis, the authors estimated the relative risk of death using conditional Poisson regression. The relative risk of death, accounting for the matching on motorcycle and adjusted for age, sex, and seat position, for a helmeted rider compared with an unhelmeted rider was 0.61 (95% confidence interval: 0.54, 0.70). The authors suggest that conditional Poisson regression is useful for the analysis of traffic crash data, where occupants are naturally matched in a vehicle and where crash-related confounders may be difficult or impossible to measure.

Accidents, Traffic↗
PubMed2002

Association of driver air bags with driver fatality: a matched cohort study.

OBJECTIVE: To estimate the association of driver air bag presence with driver fatality in road traffic crashes. DESIGN: Matched pair cohort study. SETTING: All passenger vehicle crashes in the United States during 1990-2000 inclusive. SUBJECTS: 51 031 driver-passenger pairs in the same vehicle. MAIN OUTCOME MEASURES: Relative risk of death within 30 days of a crash. RESULTS: Drivers with an air bag were less likely to die than drivers without an air bag (adjusted relative risk 0.92 (95% confidence interval 0.88 to 0.96)). This estimate was nearly the same whether drivers wore a seat belt (adjusted relative risk 0.93) or not (0.91). Air bags were associated with more protection for women (0.88 (0.82 to 0.93)), than for men (0.94 (0.90 to 0.99)). Drivers wearing a seat belt were less likely to die than unbelted drivers (0.35 (0.33 to 0.36)). Belted drivers with an air bag were less likely to die than unbelted drivers without an air bag (0.32 (0.30 to 0.34)). CONCLUSIONS: If the associations are causal the average risk of driver death was reduced 8% (95% confidence interval 4% to 12%) by an air bag. Benefit was similar for belted and unbelted drivers and was slightly greater for women. However, seat belts offered much more protection than air bags.

Accidents, Traffic↗
PubMed2002

Ampicillin use in infant fever: a systematic review.

OBJECTIVES: To estimate the prevalence of perinatal Listeria monocytogenes and enterococcal infections in outpatient febrile infants and to evaluate the need to treat with ampicillin. DATA SOURCES: Online bibliographies were searched for articles related to serious bacterial infection and fever in infants. Reference lists from selected and review articles were also examined. STUDY SELECTION: Studies that reported rates and types of bacterial infection in febrile outpatients younger than 3 months were included. Those performed outside North America, lacking results by age, or those that evaluated selected patient populations were excluded. DATA EXTRACTION: Two authors independently reviewed the selected articles for inclusion and abstracted the data. DATA SYNTHESIS: Fourteen studies, evaluating 5247 febrile outpatients, were included. The prevalences of L monocytogenes and enterococcal infections were 7.3 (binomial exact 95% confidence interval [CI], 3.5-13.3), 1.9 (95% CI, 0.6-4.4), and 5.6 (95% CI, 0.7-2.1) per 1000 febrile infants in the first, second, and third months of life, respectively. To cover 1 infant with serious bacterial infection caused by L monocytogenes and enterococcal infections, the numbers of febrile infants who would need ampicillin were estimated as 138 (95% CI, 76-288) in the first month, 527 (95% CI, 226-1621) in the second month, and 178 (95% CI, 50-1469) in the third month. Enterococcal infections occurred in all ages studied; there were no Listeria infections after 30 days of age. CONCLUSION: The empirical use of ampicillin to cover febrile infants for L monocytogenes and enterococcal infections is most justifiable in the first month of life.

Age Distribution↗
PubMed2002

Freeway speed limits and traffic fatalities in Washington State.

BACKGROUND: In 1987 individual states in the USA were allowed to raise speed limits on rural freeways from 55 to 65 mph. Analyses of the impact of the increased speed limits on highway safety have produced conflicting results. OBJECTIVE: To determine if the 1987 speed limit increase on Washington State's rural freeways affected the incidence of fatal crashes or all crashes on rural freeways, or affected average vehicle speeds or speed variance. DESIGN: An ecological study of crashes and vehicle speeds on Washington State freeways from 1974 through 1994. RESULTS: The incidence of fatal crashes more than doubled after 1987, compared with what would have been expected if there had been no speed limit increase, rate ratio 2.1 (95% confidence interval (CI), 1.6-2.7). This resulted in an excess of 26.4 deaths per year on rural freeways in Washington State. The total crash rate did not change substantially, rate ratio 1.1 (95% CI, 1.0-1.3). Average vehicle speed increased by 5.5 mph. Speed variance was not affected by the speed limit increase. CONCLUSIONS: The speed limit increase was associated with a higher fatal crash rate and more deaths on freeways in Washington State.

Accidents, Traffic↗
PubMed2002

Air bags and passenger fatality according to passenger age and restraint use.

BACKGROUND: Some children have been killed by air bags, leading to advice that young children should not sit in front of an active air bag. METHODS: We conducted a case-control study to estimate the association of passenger air bag presence with death, according to passenger age and seat belt use. We used data from crashes on U.S. public roads in 1992 through 1998. Cases (N = 20,987) were front seat passengers who died, and controls (N = 69,277) were a sample of survivors. RESULTS: Among restrained passengers, the adjusted relative risk of death for those with a passenger air bag was 0.79 (95% confidence interval [CI] = 0.66-0.94); for children 12 years or younger, the adjusted relative risk was 1.04 (0.65-1.67) [corrected], and for adults 20 years or older it was 0.75 (0.62-0.91) [corrected]. Among unrestrained passengers, the adjusted relative risk was 1.03 (CI = 0.81-1.30); for children 12 years or younger the adjusted relative risk was 1.37 (0.84-2.21) [corrected], and for adults 20 years or older it was 0.96 (0.75-1.24). CONCLUSIONS: Passenger air bags may be a hazard to unrestrained children and of little benefit to unrestrained adults. Our results support the advice that children younger than 13 years should not sit in front of an active air bag.

Accidents, Traffic↗
PubMedDate not supplied

Severe injury among Hispanic and non-Hispanic white children in Washington state.

OBJECTIVES: The authors' anecdotal experience at a regional Level I trauma center was that Hispanic children were overrepresented among burn patients, particularly among children with burns due to scalding from hot food. This study describes injury incidence and severity among Hispanic and non-Hispanic white infants, children, and adolescents with serious traumatic injuries in Washington State. METHODS: Data from the Washington State Trauma Registry for 1995-1997 were used to identify injured individuals aged < or = 19 years. Ratios of overall and mechanism-specific injury incidence rates for Hispanic children relative to non-Hispanic white children were calculated using denominator estimates derived from U.S. Census Bureau population data. Hispanic children and non-Hispanic white children were also compared on several measures of severity of injury. RESULTS: In 1995-1997, serious traumatic injuries were reported to the Registry for 231 Hispanic children aged < or = 19 years (rate: 54 per 100,000 person-years) and for 2,123 non-Hispanic white children (56 per 100,000 person-years), yielding an overall rate ratio (RR) of 1.0 (95% confidence interval [CI] 0.8, 1.1). Motor vehicle crashes and falls accounted for one-third to one-half of the injuries for each group. Infants, children, and adolescents identified as Hispanic had higher rates of injuries related to hot objects (i.e., burns) (RR=2.3; 95% CI 1.3, 4.1), guns (RR=2.2; 95% CI 1.5 to 3.3), and being cut or pierced (RR=3.5; 95% CI 2.2 to 5.5). The Hispanic group had a lower injury rate for motor vehicle accidents (RR=0.7; 95% CI 0.5, 0.9). Mortality rates were similar (RR=1.1; 95% CI 0.7, 1.7). The mean length of hospital stay was 5.5 days for the Hispanic group and 8.8 days for the non-Hispanic white group (difference=3.3 days; 95% CI -0.7, 7.4). CONCLUSIONS: The study found little difference between Hispanic and non-Hispanic white infants, children, and adolescents in the burden of traumatic pediatric injury. However, burns, guns, drowning, and being pierced/cut appeared to be particularly important mechanisms of injury for Hispanic children. More specific investigations targeted toward these injury types are needed to identify the underlying preventable risk factors involved.

Adolescent↗