Alcohol, Injury, and Risk-Taking Behavior: Data from a National Sample

The association of alcohol consumption and injury is well documented in the literature. It has also been suggested that alcohol consumption is associated with risk-taking behaviors. No studies have reported the association of alcohol consumption and risk-taking behaviors with injury across all injury types, however. Data were collected (1990) from a national probability household sample ( n = 2058; weighted n = 1150) on: injuries that required treatment during the last year; quantity and frequency (Q-F) of drinking; and behaviors associated with risk perception, risk-taking/impulsivity, and sensation seeking. The injured (12% of the sample) were more likely to be male, younger, and to report moderate and heavy drinking and more frequent drunkenness compared with those with no injuries. They were also less likely to score high on risk perception and more likely to score high on risk-taking/impulsivity and sensation seeking than those with no injuries. However, using logistic regression analysis to predict a treated injury during the last year, only the interaction term of gender by Q-F was significant, with Q-F a significant predictor of injury among males but not among females.     

Measurement of Alcohol-Involved Injury in Community Prevention: The Search for a Surrogate III

Alcohol is involved in a substantial percentage of injuries, with estimates in the United States ranging from 3% of drownings up to 50% of fatal traffic crashes. Thus, alcohol-involved injury is a natural target for prevention efforts, particularly at the community level. Although a potentially valuable target, the measurement of alcohol-involved injuries for purposes of outcome evaluation of such prevention is problematic. The consistent measurement of alcohol in the blood of injured persons is not a regular aspect of acute medical treatment Thus, alternatives are needed both for epidemiological, as well as prevention, research. This study will review three alternative measurements of alcohol-involved injury [i.e., (a) emergency room interviews and breath testing for blood alcohol concentration, (b) telephone surveys of self-reported injuries after drinking, and (c) injury surrogate derived archival data from hospital inpatient treatment]. After comparing the strengths and weaknesses of all three and investigating the sensitivity of the injury surrogate to detect changes in alcohol-involved injuries, this study concludes that the injury surrogate is a reliable, low-cost, and valid outcome measure for prevention evaluation.     

Drinking Patterns and Problems Associated with Injury Status in Emergency Room Admissions

A study of emergency room admissions at San Francisco General Hospital was undertaken to analyze the association of drinking patterns and problems with injury status. A 20% probability sample of patients admitted to the emergency room around-the-clock over a 60-day period was interviewed. Interviews were completed on 75% of those sampled ( N = 1896). Of these, 29% ( N = 555) were admitted to the emergency room for injuries, with drinkers more likely than abstainers to be admitted for injuries. Differences were found in the quantity and frequency of usual drinking and frequency of drunkenness for type and cause of injury and for prior alcohol-related accidents. Little difference was found between the injured and noninjured on social consequences of drinking or experiences associated with alcohol dependence and loss of control over drinking. Both injured and noninjured in this population reported much higher rates of frequent heavy drinking and alcohol-related problems than that found in the general population which may have masked additional associations of drinking patterns and problems with injury status.     

Injury and the Role of Alcohol: County-Wide Emergency Room Data

The purpose of this study is to describe variables associated with injury in an emergency room (ER) sample that is representative of an entire U.S. county. A probability sample ( n = 3717) of ER patients from the county hospital, 3 of the 0 community hospitals, and the three health maintenance organization hospitals in a single Northern California county were breathalyzed and interviewed at the time of the ER visit. Injured were most likely to consume only 1 or 2 drinks within el hr of injury occurrence. Twenty-three percent reported feeling drunk at the time of the event, and of these, 45% felt the event would not have happened if they had not been drinking. Breathalyzer reading, feeling drunk at the time of the event, and quantity-frequency (Q-F) of usual drinking were found to be predictive of admission to the ER with an injury, whereas breathalyzer reading, Q-F, and being injured in someone's home were predictive of reporting drinking prior to injury. Although feeling drunk at the time of the event and usual drinking patterns are predictive of injury occurrence, drinking prior to the event may not entail large quantities of alcohol consumed, but relatively small amounts consumed in close proximity to the injury event. These alcohol consumption variables may vary, however, depending on the type, cause, and severity of injury.     

Alcohol effects on motor vehicle crash injury

CONTEXT: Although alcohol is frequently present in injured patients, whether it exacerbates injury and whether tolerance to alcohol changes such a relationship is less clear. Most clinical studies do not consider other important predictors of injury, making interpretation of their findings problematic. OBJECTIVE: To examine alcohol's role in injuries, taking into account other important factors, and to examine the effect of tolerance, if any. DESIGN: Prospective cohort study. SETTING: University hospital and community hospital emergency departments and morgue. PATIENTS: 1362 Motor Vehicle Crash patients age >/=18, treated and released, admitted, and deceased. MAIN OUTCOME MEASURES: Excess injury measured by Injury Severity Scale (ISS) 90, Weighted Revised Trauma Score (WRTS), and G-Score. RESULTS: Using regression analysis, the best predictors of injury severity were vehicle crush (TAD), safety belt use, and their interaction, and age. Alcohol use further predicted injury. Using the final regression model, the effect of alcohol was to increase ISS90, on average, by about 30% (from a predicted ISS90 of 5.1 to 6.8, all else being equal). The adjusted odds ratio for serious injury (ISS90>15), was 1.59 for a patient with a positive blood alcohol concentration (alc+) compared to a alc- patient. This potentiating effect is seen even for patients with low levels of alcohol (<22 mmol/liter; <0.100 BAC) but is not linear with increasing alcohol level. Tolerance to alcohol did not affect the potentiation of injury by alcohol. CONCLUSION: When other relevant variables are considered, alcohol increases injury, but the effects of alcohol level and alcohol tolerance are less clear. These findings have important implications for injury prevention, treatment, and research.     

Injury risk among medically identified alcohol and drug abusers

BACKGROUND: Although nonfatal injury prevalence is higher among substance abusers than in the general population, few studies have estimated the injury risk for clinically recognized substance abusers. The extant studies, moreover, analyze rates of visits for injury treatment rather than rates of injury events. This study estimates the excess risk of medically treated and hospitalized nonoccupational injury for people under age 65 with medically identified substance abuse problems and private health care coverage. METHOD: We conducted a retrospective cohort study by using medical claims data from Medstat Systems, Inc., with a longitudinal database of health care claims for 1.5 million people with health care coverage from 70 large corporations. Claims histories for anyone who had an alcohol-related or drug-related primary or secondary diagnosis during 1987 to 1989 were analyzed. A random sample was selected from the remaining people without a substance abuse diagnosis in their medical records. Injury rates were compared among groups. We used logistic regression to estimate odds of medically treated and hospitalized injury, controlling for demographics. RESULTS: Medically identified substance abusers had an elevated risk of injury in a 3-year period; alcohol and drug abusers had the highest risk (58%), followed by drug-only abusers (49%), alcohol-only abusers (46%), and controls (38%). Alcohol and drug abusers were almost four times as likely to be hospitalized for an injury in a 3-year period when compared with controls. Injury risks were elevated substantially more for female then male substance abusers. CONCLUSIONS: This study greatly improves on available information about the risk of injury for drug and multiple-substance abusers. Medically identified substance abusers, especially adult women, have a higher probability of injury, more hospitalized injuries, and more injury episodes per person injured than nonabusers. More aggressive identification and subsequent treatment of female substance abusers appear warranted.     

Deliberate self-harm and relationship to alcohol use at an emergency department in eastern Taiwan

Suicide incidence has increased dramatically in recent years in Taiwan. In 2004, 3,468 lives were lost due to suicide and the total mortality was 15.3/100,000. It is well known that alcohol drinking raises the risk of deliberate self-harm (DSH), especially among psychologically distressed subjects. This study investigated the characteristics of DSH patients and their association with acute alcohol drinking. Since 2004, an injury surveillance system has been set up in a medical center, collecting the minimal information recommended by the World Health Organization. Attending nurses collected information and assessed each injured patient as to whether he/she smelled of alcohol. Medical records of DSH injuries were reviewed for confirmation of any prior DSH and any known mental disorder was checked. Of 11,837 injuries, 123 (1.0%) were DSH. Those who were first-time DSH patients (n = 115) were studied. About half of the patients were female and 83.5% were aged between 20 and 54 years. More than half of the DSH incidents occurred at home and 80.1% cases were stabbing or cutting injuries. Injuries were defined as alcohol-related based on the report of "alcohol odor' or "intoxicated' by the nurse or a positive blood alcohol test. In total, 55 (47.8%) DSH injuries were found to be alcohol-related. The proportion of alcohol-related injuries was highest (60.0%) in the age range 45-64 years. Of those patients who tested positive for alcohol (n = 21), the mean blood alcohol concentration was 211.2 mg/dL (standard deviation, 79.1). Most subjects were discharged from the emergency department (75.7%). Only 20 DSH patients (17.1%) went on to receive a psychiatric consultation. DSH is not uncommon in eastern Taiwan. Half of our cases were associated with alcohol use. Males had the same risk of injuring themselves and were more likely than females to adopt "severe" methods to injure themselves. Further studies into the causes of DSH or parasuicide attempts are needed. Psychiatric consultation is essential in caring for DSH patients and in preventing suicide. ADSH injury also offers an opportunity to recognize alcohol problems.     

Emergency Department Patients With Assault Injuries: Previous Injury and Assault Convictions

Study objective: To compare the incidence of previous assault injury and assault conviction of patients presenting to the ED with assault injuries and the incidence of assault injury and conviction in nonassaulted control patients. Methods: We conducted a retrospective, medical record–based case-control study of ED patients with assault injuries and matched controls presenting with medical and surgical problems unrelated to assault. The setting was the ED of a 900-bed teaching hospital and Level I trauma center in an urban area. Our subjects were 50 patients who presented as victims of blunt trauma, 50 patients who presented with penetrating trauma, and 100 control subjects matched by age, sex, and ZIP code who presented concurrently with nonassault complaints. Results: The overall rate of previous assault injury was 35% and did not differ between cases and controls. Fifty-three patients had a history of criminal conviction, and 23 had a history of conviction for assault. Fewer patients presenting with assault injuries than controls had a history of conviction for assault (odds ratio [OR], .3; P<.02). Patients with penetrating injuries had the lowest incidence of assault conviction (OR, .13; P<.02). The subgroup of case subjects with criminal records had a higher rate of previous injury than those without records (P<.003). Conclusion: ED patients with assault injuries did not have a history of assault injuries exceeding that of controls and were less likely to have been convicted of assault. Violence-prevention programs should be directed toward a broader population of ED patients instead of narrowly focusing on victims of assault. [Moscovitz H, Degutis L, Bruno GR, Schriver J: Emergency department patients with assault injuries: Previous injury and assault convictions. Ann Emerg Med June 1997; 29:770-775.]     

Alcohol and Fatal Injury: The Use of Routinely Collected Fatality Data in Community Prevention Evaluation

BACKGROUND: This study analyzed patterns of alcohol involvement among coroners' cases (which typically include blood alcohol content information) to develop a method for weighting death-certificate cases (which typically do not include blood alcohol content information) for likelihood of alcohol involvement for purposes of alcohol-involved injury intervention evaluation. METHODS: The coroners' data analyzed here were collected from four California communities and correspond to all injury coroner cases between 1987 and 1996 in those communities. The death-certificate data were provided by the State of California, Department of Health Services, and correspond to all injury deaths occurring in that state between 1980 and 1996. Each injury fatality in the death-certificate data was assigned a probability of alcohol involvement based upon the coroners' data. These were then summed to provide an estimate of, or "surrogate measure" for, the total number of alcohol-involved fatal injuries per 10,000 California residents aggregated across the state of California by month for the period from January 1980 to 1990. As a test of this estimate, we examined its responsiveness to an intervention designed to reduce alcohol-involved injuries which was implemented in California in 1990 using a time series analysis technique (ARIMA) that corrects for serial autocorrelation typically found in time ordered data. RESULTS: This analysis found an effect during the postintervention period (p = 0.046). An alternative model testing for intervention effects on all injury fatalities did not find an effect. CONCLUSIONS: This surrogate measure seems responsive to intervention effects and may provide a useful tool for interventions designed to reduce alcohol-involved injuries.     

Extreme College Drinking and Alcohol-Related Injury Risk

Background: Despite the enormous burden of alcohol‐related injuries, the direct connection between college drinking and physical injury has not been well understood. The goal of this study was to assess the connection between alcohol consumption levels and college alcohol‐related injury risk. Methods: A total of 12,900 college students seeking routine care in 5 college health clinics completed a general Health Screening Survey. Of these, 2,090 students exceeded at‐risk alcohol use levels and participated in a face‐to‐face interview to determine eligibility for a brief alcohol intervention trial. The eligibility interview assessed past 28‐day alcohol use and alcohol‐related injuries in the past 6 months. Risk of alcohol‐related injury was compared across daily drinking quantities and frequencies. Logistic regression analysis and the Bayesian Information Criterion were applied to compute the odds of alcohol‐related injury based on daily drinking totals after adjusting for age, race, site, body weight, and sensation seeking. Results: Male college students in the study were 19% more likely (95% CI: 1.12–1.26) to suffer an alcohol‐related injury with each additional day of consuming 8 or more drinks. Injury risks among males increased marginally with each day of consuming 5 to 7 drinks (odds ratio = 1.03, 95% CI: 0.94–1.13). Female participants were 10% more likely (95% CI: 1.04–1.16) to suffer an alcohol‐related injury with each additional day of drinking 5 or more drinks. Males (OR = 1.69, 95% CI: 1.14–2.50) and females (OR = 1.81, 95% CI: 1.27–2.57) with higher sensation‐seeking scores were more likely to suffer alcohol‐related injuries. Conclusions: College health clinics may want to focus limited alcohol injury prevention resources on students who frequently engage in extreme drinking, defined in this study as 8+M/5+F drinks per day, and score high on sensation‐seeking disposition.     

Use of ICD-9-CM Codes in the Estimation of Alcohol-Involved Injury: Search for a Surrogate II

This study presents a follow-up analysis of 22,427 injury cases drawn from the California Regional Trauma Registry. Whereas the earlier analysis developed a surrogate for alcohol-involved injuries using E-codes as reflective of injury type, this analysis explores the possibility of using ICD-9-CM diagnosis codes that have a longer history and are available in more jurisdictions. Findings reported herein indicate that the original demographic patterns predicting testing and alcohol involvement patterns were maintained in ICD-9-CM diagnostic code-based models. Moreover, although variables representing demographic background, time of day, and day of week clearly were the most powerful model predictors, ICD-9-CM diagnostic codes reflecting physician assessment that the patient had a chronic alcohol problem did improve the fit of models, and thus provide additional information concerning testing and blood alcohol concentration patterns. In contrast, ICD-9-CM diagnostic codes reflecting the specific nature of the injury, although statistically significant, explained little additional variability in alcohol involvement. Nevertheless, the overall model did accurately classify ˜75% of those in the sample for whom blood alcohol concentration status information was available, suggesting its appropriateness for surrogate development.     

Drinking Patterns and Problems and Drinking in the Event: An Analysis of Injury by Cause Among Casualty Patients

The association of alcohol and injury might be expected to vary by the specific cause of injury, but few studies have examined such associations across all causes of injury coming from the same population, largely because of the lack of a sufficient number of cases. This study examines the association of drinking patterns and problems and drinking-in-the-injury-event for six mutually exclusive causes of injury (falls, penetrating trauma, motor vehicle accidents, fires, violence, and other causes) in a merged sample of 3109 patients from four emergency room/trauma center studies that used identical study methodology. The predictive value of drinking and demographic variables are examined separately for each cause of injury, and variables predictive of reporting drinking before the event, feeling drunk at the time of injury, and attributing a causal association of drinking and the injury. Injuries sustained from violence and falls had the greatest association with drinking variables, with those with positive breathalyzer readings, and those who reported drinking before injury, frequent heavy drinking, and frequent drunkenness overrepresented in these two causes. Those who reported a larger number of drinks consumed before injury and those who reported feeling drunk at the time were also overrepresented among those with injuries related to violence and falls. A larger proportion than expected of those who attributed a causal association of drinking with the event sustained injuries related to violence, whereas a smaller proportion sustained injuries from falls. Demographic characteristics were more predictive than drinking characteristics of each cause of injury, whereas drinking characteristics, particularly positive breathalyzer readings, were more predictive of drinking before specific causes of injury. These data provide information that may be useful in developing brief interventions for the prevention of alcohol-related injuries in the emergency room or trauma center setting.     

Adolescent risk taking and self-reported injuries associated with substance use

OBJECTIVE: To examine the incidence of adolescent substance use at the time of injury and its relation to risk-taking behavior. METHOD: A total of 643 male and 782 female 9th through 12th grade students at three high schools anonymously completed surveys on any injuries that had occurred in the prior 6 months associated with substance use and risk-taking behavior. RESULTS: Males reported a higher incidence of injuries related to alcohol or other drugs than females (17.3% vs. 13%). The 17 year olds reported more injuries related to substance use than 14 or 15 year olds (20.2% vs. 14.4% and 15%, respectively). A logistic regression analysis revealed that the odds of a substance use-related injury increased approximately sixfold when adolescents reported engaging in risk-taking behavior. CONCLUSION: A significant portion of adolescents (approximately 15%) reported injuries associated with substance use. Adolescents who reported a history of risk-taking behaviors were much more likely to report substance use-related injuries.     

Alcohol and injuries resulting from violence: a review of emergency room studies

This paper reviews emergency room (ER) studies from a number of countries which have reported findings related to the association of alcohol and injuries resulting from violence. Special attention is given to those studies which used probability samples of patients which were representative of the population served by the emergency room facility where the data were collected, and which compared those admitted to the ER with violence-related injuries with those admitted to the same ER during the same period of time with injuries unrelated to violence. Those with violence-related injuries were more likely to be admitted to the ER with a positive blood alcohol concentration, to report drinking prior to the event, to report more frequent heavy drinking and to report more alcohol-related problems than those admitted with injuries from other causes.     

A Comparative Analysis of Alcohol in Fatal and Nonfatal Bicycling Injuries

Bicycling is the leading cause of recreational injury, resulting in more than half a million emergency department visits and about 900 deaths each year in the United States. Previous research on bicycling injury was conducted predominantly in children and focused on the effectiveness of safety helmets. Few studies have examined the role of alcohol in bicycling injuries. This study examined the magnitude of and factors related to alcohol involvement in fatal and nonfatal bicycling injuries, and tested the hypothesis that alcohol intoxication is associated with significantly increased likelihood of fatality given a serious bicycling injury. Medical examiner data on all fatally injured bicyclists aged 10 years or older from 1987 to 1994 in Maryland (fatal cases, n= 63) were compared with trauma registry data on all injured bicyclists who were treated at a regional trauma center during the same time period (nonfatal cases, n= 253) on variables related to blood alcohol concentrations (BACs), demographic characteristics, and injury circumstances. The fatal cases were more likely than the nonfatal cases to have positive BACs (30% vs. 16%, p < 0.01). and to be legally intoxicated (is., BACs ≥ 0.10%) (22% vs. 13%, p < 0.01). For both fatal and nonfatal cases, intoxication was more prevalent among victims who were male, aged 20 to 39 years, or who were injured at nighttime (7:00 PM to 6:59 AM). Bicyclists who died at the scene were four times as likely as those who died at hospitals to be legally intoxicated (35% vs. 9%, p < 0.02). Given a serious bicycling injury, intoxication was associated with significantly increased likelihood of fatality, with an adjusted odds ratio of 2.8 (95% confidence interval, 1.3 to 6.3). This increased likelihood of fatality was probably due in part to the fact that the rate of helmet use at the time of injury among the intoxicated was much lower than among the sober (vs. 31%, p < 0.05). Results indicate that alcohol plays an important role in fatal and serious bicycling injuries. Preventing intoxicated biking should be incorporated into helmet campaigns and other bicycle safety programs.     

Urinary Interleukin‐18 and Urinary Neutrophil Gelatinase‐associated Lipocalin Predict Acute Kidney Injury Following Pulmonary Valve Replacement Prior to Serum Creatinine

Background. It is becoming increasingly recognized that manifestations of congenital heart disease (CHD) extend beyond the cardiovascular system. The factors contributing to renal dysfunction in patients with CHD are multifactorial, with acute kidney injury (AKI) at time of cardiac surgery playing a major role. AKI is often diagnosed based on changes in serum creatinine and estimated glomerular filtration rate (eGFR). Such measurements are often late and imprecise. Recent data indicate that urinary biomarkers interleukin‐18 (IL‐18) and neutrophil gelatinase‐associated lipocalin (NGAL) are earlier markers of AKI. We sought to determine the efficacy of urinary IL‐18 and NGAL for detecting early AKI in patients undergoing surgical pulmonary valve replacement (PVR). Methods. Twenty patients presenting for surgical PVR with a history of previous repair of a conotruncal anomaly were enrolled. Preoperative clinical data were measured and urine samples and serum creatinine were collected at 6, 12, 24, and 72 hours post bypass. Urine was evaluated for NGAL and IL‐18. AKI was determined using the Risk, Injury, Failure, Loss and End Stage Renal Disease (RIFLE) classification system. Results. Using the RIFLE classification system, seven patients (35%) were found to have AKI defined as a drop in the eGFR or an increase in serum creatinine. All seven patients with AKI had marked increase from preoperative baseline in urine IL‐18 (sixfold) and NGAL (26‐fold). Using NGAL and IL‐18, AKI was detected at 6 hours postoperatively, resulting in AKI being identified 12–36 hours prior to detection by conventional methods. No preoperative predictors for AKI were identified. Conclusion. Both NGAL and IL‐18 are early predictive biomarkers of AKI, and both increase in tandem after surgical PVR. Importantly, both rise before an increase in creatinine or a decrease in eGFR is present. Monitoring both biomarkers may allow for earlier detection and subsequent interventions to prevent AKI at time of surgery for CHD.     

Hospital-admitted injury attributable to alcohol

Background: Primary data collection has established that alcohol causes injuries treated in the emergency department. No comparable data exist for injuries admitted to hospital. Data on the injury risks of heavy drinkers relative to other drinkers also are sparse. Methods: We estimated (i) whether regular heavy drinkers have higher hospitalized injury risks than other people when alcohol‐negative and (ii) how much hospitalized injury risk of regular heavy drinkers and other drinkers rises when alcohol‐positive. We combined national alcohol consumption data with alcohol metabolism rates to estimate hours spent alcohol‐positive versus alcohol‐negative during a year for heavy drinkers versus other people. A literature review provided hospitalized nonfatal injury rates for these groups by alcohol involvement. Results: Relative to other alcohol‐negative people aged 18 and older, heavy drinkers have an estimated relative risk of hospitalized injury of 1.4 when alcohol‐negative and 4.3 when alcohol‐positive. Others have an estimated relative risk of 1.0 when alcohol‐negative and 6.8 when alcohol‐positive. Thus, alcohol greatly raises injury risk. The excess risk patterns persist for a wide range of sensitivity analysis values. Of hospitalized injuries, an estimated 21% are alcohol‐attributable including 36% of assaults. Conclusions: Drinking alcohol is a major cause of hospitalized injury. Heavy drinkers lead risky lifestyles. They tolerate alcohol better than most drinkers, but their injury risks still triple when they drink. Our approach to attribution is a valuable complement to more costly, more precise approaches that rely heavily on primary data collection. It works for any severity of injury. Applying it only requires an existing alcohol consumption survey plus data on alcohol involvement in targeted injuries.     

Adolescent Risk Taking and Self-Reported Injuries Associated with Substance Use

Objective: To examine the incidence of adolescent substance use at the time of injury and its relation to risk-taking behavior. Method: A total of 643 male and 782 female 9th through 12th grade students at three high schools anonymously completed surveys on any injuries that had occurred in the prior 6 months associated with substance use and risk-taking behavior. Results: Males reported a higher incidence of injuries related to alcohol or other drugs than females (17.3% vs. 13%). The 17 year olds reported more injuries related to substance use than 14 or 15 year olds (20.2% vs. 14.4% and 15%, respectively). A logistic regression analysis revealed that the odds of a substance use–related injury increased approximately sixfold when adolescents reported engaging in risk-taking behavior. Conclusion: A significant portion of adolescents (approximately 15%) reported injuries associated with substance use. Adolescents who reported a history of risk-taking behaviors were much more likely to report substance use–related injuries.     

Validity of self-reported alcohol consumption in nondependent drinkers with unintentional injuries

BACKGROUND: Self-report has become an anchor for alcohol assessment in the acute and primary care populations. The purpose of the study was to determine the validity of self-reported alcohol consumption after unintentional injuries in hospitalized, nondependent drinkers. METHODS: Non-alcohol-dependent subjects 18 years of age and older with unintentional injuries (n = 209) were enrolled in the study and were interviewed if they had either an admitting blood alcohol concentration (BAC) > or = 10 mg/dl (0.01 g/dl) or a positive screen for a history of problem drinking. The self-reported number of standard drinks, time that drinking commenced, sex, and weight were used to calculate estimated blood alcohol concentration (EBAC), which was then compared to the admission BAC. RESULTS: We had data to calculate the EBAC on 141 of the 209 subjects. Seven men and no women with positive (> or = 10 mg/dl) BAC denied drinking. Of the 134 subjects for whom we had data to calculate EBAC and who acknowledged drinking, mean BAC was 147.06 mg/dl and mean EBAC was 68.66 mg/dl. For women (n = 30), mean BAC was 149.53 mg/dl and mean EBAC was 114.67 mg/dl; for men (n = 104), mean BAC was 146.35 mg/dl and mean EBAC was 55.38 mg/dl. The Spearman's p between laboratory BAC and EBAC was 0.461 (p < 0.001) for all subjects (n = 134), 0.275 (NS) for women (n = 30), and 0.532 (p < 0.001) for men (n = 104). For women and men separately, multiple regression analyses were performed to predict BAC by using weight and reported number of drinks. For women, weight and number of drinks accounted for 3% of the variance in laboratory BAC [r = 0.181, F(2,47) = 0.797,p = NS]. In contrast, for men these same predictors accounted for 34% of the variance [r = 0.585, F(2,135) = 35.203,p < 0.001). CONCLUSIONS: Most nondependent patients with unintentional injury acknowledged drinking before injury. After injury, women and men have different patterns of reporting their drinking, with men more frequently underreporting but reporting more accurately and women more random in their self-reports.