New This
Week
in theResource Library
November 3, 2000
Part 1
See Part 2 for the additional categories
General/Overlapping
- Theodorou DA; Velmahos GC; Souter I; Chan LS; Vassiliu P;
Tatevossian R; Murray JA; Demetriades D. Fetal death after trauma in pregnancy. Am Surg 2000 Sep;66(9):809-12.
ABSTRACT: Trauma in pregnancy places the mother and fetus at risk. The
objective of this study is to identify risk factors independently associated
with acute termination of pregnancy and/or fetal mortality after trauma. The
medical and trauma registry records of 80 injured pregnant patients were
reviewed. Data were collected and then analyzed by univariate and
multivariate analysis. Three patients died (3.7%), 23 had the pregnancy
acutely terminated (30%), and 14 suffered fetal death (17.5%). The only
independent risk factors for fetal mortality were an Injury Severity Score
(ISS) > or =9 and a nonviable pregnancy (<23 weeks). The combination of both
risk factors increased the likelihood of fetal mortality by fivefold over
that of patients without either risk factor. Maternal hemodynamic parameters
did not predict fetal loss. Two patients lost their fetuses despite
insignificant trauma (ISS = 1) and normal hemodynamic parameters, whereas
eight delivered normal babies despite major trauma (ISS > or = 16).
Hemodynamic stability on admission does not predict fetal mortality.
Although the presence of moderate to severe injuries (ISS > or = 9)
increases the likelihood of fetal mortality, this complication may occur
even with insignificant trauma. Close maternal and fetal monitoring is
justified, regardless of maternal hemodynamic presentation or severity of
injury.
- Al-West T; Rivara FP; Cummings P; Jurkovich GJ; Maier RV. Harborview assessment for risk of mortality: an improved measure of injury severity on the basis of ICD-9-CM. J Trauma 2000 Sep;49(3):530-40;.
ABSTRACT: BACKGROUND: There have been several attempts to develop a scoring
system that can accurately reflect the severity of a trauma patient's
injuries, particularly with respect to the effect of the injury on survival.
Current methodologies require unreliable physiologic data for the assignment
of a survival probability and fail to account for the potential synergism of
different injury combinations. The purpose of this study was to develop a
scoring system to better estimate probability of mortality on the basis of
information that is readily available from the hospital discharge sheet and
does not rely on physiologic data. METHODS: Records from the trauma registry
from an urban Level I trauma center were analyzed using logistic regression.
Included in the regression were International Classification of Diseases-9th
Rev (ICD-9CM) codes for anatomic injury, mechanism, intent, and preexisting
medical conditions, as well as age. Two-way interaction terms for several
combinations of injuries were also included in the regression model. The
resulting Harborview Assessment for Risk of Mortality (HARM) score was then
applied to an independent test data set and compared with Trauma and Injury
Severity Score (TRISS) probability of survival and ICD-9-CM Injury Severity
Score (ICISS) for ability to predict mortality using the area under the
receiver operator characteristic curve. RESULTS: The HARM score was based on
analysis of 16,042 records (design set). When applied to an independent
validation set of 15,957 records, the area under the receiver operator
characteristic curve (AUC) for HARM was 0.9592. This represented
significantly better discrimination than both TRISS probability of survival
(AUC = 0.9473, p = 0.005) and ICISS (AUC = 0.9402, p = 0.001). HARM also had
a better calibration (Hosmer-Lemeshow statistic [HL] = 19.74) than TRISS (HL
= 55.71) and ICISS (HL = 709.19). Physiologic data were incomplete for 6,124
records (38%) of the validation set; TRISS could not be calculated at all
for these records. CONCLUSION: The HARM score is an effective tool for
predicting probability of in-hospital mortality for trauma patients. It
outperforms both the TRISS and ICD9-CM Injury Severity Score (ICISS)
methodologies with respect to both discrimination and calibration, using
information that is readily available from hospital discharge coding, and
without requiring emergency department physiologic data.
- Cummings P. Should your neighbor buy a gun? Epidemiology. 2000 Nov;11(6):617-18.
ABSTRACT: Cummings provides commentary on the Miller et al. report and suggests that as with infectious disease investigations, researchers should seek information about persons other than the individuals who are the main focus of the research. In understanding the risks and benefits of firearms, we might want to assess not only whether having a gun is associated with an outcome such as being murdered, but we might also want to assess the gun ownership status of the neighbors of study subjects. An individual's risk of death might be influenced by the armament status of his neighborhood, independent of the amount of crime in the neighborhood.
- Ball D. Ships in the night and the quest for safety. Injury Control and Safety Promotion 2000; 7(2):83-96.
Abstract: Injury prevention, by its nature, is a highly multidisciplinary field and so is of direct or indirect interest to an exceptionally wide professional as well as lay audience. Although a safer society likely constitutes a common vision for most of those concerned with injury prevention, the concept of safety, when scrutinized, can be seen to be perceived and effected in different ways by different professional groups. In extreme cases, divergent approaches may continue to co-exist by becoming cocooned in worlds of their own, setting their own injury prevention priorities without much heed for what happens elsewhere. This diversity, because it is often only tacitly acknowledged if at all, can give rise to misunderstanding and even conflict between those with otherwise shared goals, and may also account for much of the public controversy frequently associated with safety issues.
A further consequence of the existence of discrete and contrasting notions of safety is the introduction of an element of randomness into the overall societal process of achieving safety, which may dilute and, in some cases, even subvert the primary intention. This arises because of the unpredictability of the outcome where competing concepts are engaged. It is argued here that inter-professional discord is an impediment to the pursuance of safety, and that greater communication between professional disciplines and agencies organized along professional lines, and between professionals and the wider public, about the fundamental choices involved in injury prevention would enable safety to be pursued in a more effective manner, and that this should be in everyone's interest.
- Cryer PC, Jarvis S, Edwards P, Langley J. How can we reliably measure the occurrence of non-fatal injury? International Journal for Consumer & Product Safety 1999; 6(4):183-191.
Abstract: INTRODUCTION. In England, there is no reliable indicator for measuring the occurrence of non-fatal injury. As a consequence, we do not know whether the rates of non-fatal injury are increasing or decreasing.
PURPOSE. This paper addresses two questions:what criteria should an indicator of non-fatal injury satisfy, and can we identify an indicator that satisfies these criteria?
METHOD. Criteria for a good indicator of non-fatal injury are postulated, and an indicator based on serious long-bone fractures is proposed. Inferences from the literature and the various non-fatal injury data to which we have access are used to justify the criteria, and to test the proposed indicator of serious injury against the criteria.
FINDINGS. There is significant evidence to justify the use of the following criteria to assess indicators of non-fatal injury:the indicator should reflect the occurrence of injury satisfying some case definition of anatomical damage; the injury cases ascertained should be important in terms of incapacity, impairment, disability, quality of life, cost, and/or threat-to-life; cases should be completely ascertained from routinely or easily collected data; and the probability of a case being ascertained should be independent of social, health services supply and access factors. Our analysis indicates that an indicator based on serious long-bone fracture admitted to hospital is likely to satisfy each of these criteria for a good indicator.
CONCLUSION. An indicator of non-fatal injury occurrence based on serious long-bone fractures exhibits favorable characteristics when judged against our criteria for a good indicator.
Keywords: Injury, non-fatal injury, indicator criteria, incidence measurement.
- Harrison J. Injury classification: balancing continuity and utility. Injury Control and Safety Promotion 2000; 7(1):51-63.
Abstract: The approach to classifying injury and its causes in the International Classification of Diseases changed radically between ICD5 and ICD6. It has changed relatively little in the subsequent four revisions and fifty years. ICD6 introduced separate chapters for "injury and poisoning" and "external causes", and the main groups in each of those chapters.
Injury research has emerged as a discipline in the period since ICD6 was developed. Major themes are conceptual frameworks of etiology and prevention, the empirical measurement of injury severity, and population-based and community injury prevention techniques.
ICD-10 (in common with ICD-9) reflects these developments to a very limited extent. A response to limitations of the ICD for purposes of injury prevention and control was the development, particularly in the 1980s and 1990s, of special-purpose classifications of characteristics of events that result in injury. Recognition of strong commonality among several of these 'multi-axial' systems led to a view that an international system embodying shared characteristics was achievable and worthwhile. The draft ICECI is the latest outcome of this work.
Compatibility with ICD-10 is a design criterion for ICECI because of the continuing central importance of the ICD for health classification. The precise meaning of "compatibility" in this context has not been resolved. At one extreme, "compatibility" could mean limiting ICECI simply to the ICD-10 external cause codes with subdivision of existing categories, and perhaps some additional data items that do not overlap conceptually with ICD-10. At other extremes, ICECI could be developed without specific reference to categories in ICD-10, or ICECI could replace the existing ICD external cause classification.
It is not practicable to map every ICD-10 three-character external cause category to a unique equivalent combination of codes in a multi-axial system, mainly due to conceptual inconsistencies in the ICD-10 external cause classification. More limited mapping is possible and could be designed to ensure that data coded to ICECI could be grouped to be equivalent to important ICD external cause categories.
The way chosen for classification of external causes should be one that recognises contemporary information requirements in the fields of injury prevention and control as well as the desirability of continuity in long-term monitoring of important categories of injury. Field-testing and consultation with data users will determine whether ICECI meets these criteria well enough to warrant its adoption as a member of the ICD family of classifications.
- Wagner AK; Sasser HC; Hammond FM; Wiercisiewski D; Alexander J. Intentional traumatic brain injury: epidemiology, risk factors, and associations with injury severity and mortality. J Trauma 2000 Sep;49(3):404-10.
ABSTRACT: BACKGROUND: Intentional injury is associated with significant
morbidity and mortality and has been associated with certain demographic and
socioeconomic groups. Less is known about the relationship of intentional
traumatic brain injury (TBI) to injury severity, mortality, and demographic
and socioeconomic profile. The objective of this study was to delineate
demographic and event-related factors associated with intentional TBI and to
evaluate the predictive value of intentional TBI on injury severity and
mortality. METHODS: Prospective data were obtained for 2,637 adults
sustaining TBIs between January 1994 and September 1998. Descriptive,
univariate, and multivariate analyses were conducted to determine the
predictive value of intentional TBI on injury severity and mortality.
RESULTS: Gender, minority status, age, substance abuse, and residence in a
zip code with low average income were associated with intentional TBI.
Multivariate analysis found minority status and substance abuse to be
predictive of intentional injury after adjusting for other demographic
variables studied. Intentional TBI was predictive of mortality and anatomic
severity of injury to the head. Penetrating intentional TBI was predictive
of injury severity with all injury severity markers studied. CONCLUSION:
Many demographic variables are risk factors for intentional TBI, and such
injury is a risk factor for both injury severity and mortality. Future
studies are needed to definitively link intentional TBI to disability and
functional outcome.
- Miller TR, Lawrence B, Jensen A, Fisher D, Zamula W. Estimating the costs of non-fatal consumer product injuries in the United States. Injury Control and Safety Promotion 2000; 7(2):97-113.
Abstract: This paper describes a data-driven injury cost model (ICM) developed to estimate the costs associated with non-fatal consumer product injuries. The modeling effort combines information by diagnosis from the US Consumer Product Safety Commission's National Electronic Injury Surveillance System (NEISS) and 17 other large data sets. The ICM contains four aggregated cost components: (1) medical costs, (2) work losses, (3) quality of life and pain and suffering costs, and (4) product liability insurance administration and litigation costs. The ICM estimates societal costs, which are broader than costs to any individual group, such as victims, insurers, or product manufacturers.
Costs associated with consumer product injuries are estimated to be approximately $500 billion in 1996, accounting for nearly one-third of the total annual injury costs. We examine injury costs in several ways, including by major product category, by sex and age of victims, by body part injured, by injury diagnosis, and by highest level of medical treatment received. We also rank the 10 leading consumer products that account for injury costs overall and within different age groups. Products such as stairs and floors are among the top 10 for all age groups. Other products, however, are more closely tied to injuries at particular stages of life (e.g., infant/toddler, child, young adult, elderly). These cost estimates are useful in assessing which products and types of injuries impose the greatest costs on society and for identifying areas for focused injury prevention efforts.
- Cryer PC; Jarvis SN; Edwards P; Langley JD. Why the government was right to change the 'Our Healthier Nation' accidental injury target. Public Health 2000 Jul;114(4):232-7.
ABSTRACT: We congratulate the current UK Government on their inclusion of
accidental injury as one of the national targets in the White Paper: Saving
Lives-Our Healthier Nation (OHN). We had concerns about the particular
target that was proposed in the Green Paper: 'to reduce the rate of
accidents-here being defined as those which involve a hospital visit or
consultation with a family doctor-by at least a fifth'. The
limitations of this target were: firstly, it would focus attention on minor
injury and so not reflect the main burden of injury; and secondly, that
ascertainment of cases would be influenced by social factors as well as
provision of service and access factors. The new target stated in Saving
Lives also has its limitations since it will be influenced by service
factors. This target is to reduce by 10% the rate of serious injury, defined
as injury resulting in four or more days in hospital. We have proposed the
use of an alternative indicator of unintentional injury occurrence, based on
serious long bone fracture admitted to the hospital. This alternative
indicator is based on the occurrence of serious rather than minor injury. It
is likely that a high proportion of cases of these injuries can be
identified from existing data sources. Ascertainment of cases is likely to
be independent of social, service or access factors. Finally, these injuries
are associated with significant long term outcomes including disablement,
reduced functional capacity and reduced quality of life. It does have the
limitation that it does not measure all serious injury. Such a measure is
much more difficult to achieve. Further improvements to our proposed
indicator could be made in a number of ways, through investigating an
extended definition of the indicator to include a range of other serious
injuries, improving the quality of existing data, making other data sources
available, including outpatient data, and making serious injury a notifiable
disease.
- Parkkari J; Kannus P; Niemi S; Koskinen S; Palvanen M; Vuori I;
Jarvinen M. Childhood deaths and injuries in Finland in 1971-1995. Int J Epidemiol 2000 Jun;29(3):516-23.
ABSTRACT: BACKGROUND: This study examined the recent nationwide trends for
the absolute number and the age- and sex-specific incidence rates of the
fatal and serious non-fatal injuries among 0-14 year old children in Finland
in 1971-1995. METHODS: We selected from Official Cause-of-Death Statistics
and National Hospital Discharge Register children aged 0-14 years who died
or required treatment at a hospital department because of an injury in
1971-1995. The number of Finnish children was 1.1 million in 1971, and 1.0
million in 1995. RESULTS: During the entire study period injuries were the
leading cause of death in children aged 1-14 years, but not in infants.
However, in these years the incidence (per 100 000 people) of fatal injuries
in Finnish children decreased considerably in all age groups and both sexes,
in girls from 20.1 in 1971 to 4.6 in 1995, and in boys from 36.7 in 1971 to
9.3 in 1995. In 1995, 41% of all the injurious deaths among 0-14 year old
Finnish children were motor vehicle accidents, 12% were drownings, and 24%
intentional injuries. The overall number and incidence of serious non-fatal
injuries among Finnish children showed no clear trend change in 1971-1995.
The mean hospitalization time of injured children shortened between 1971 and
1995, from 7.4 days to 2.7 days. CONCLUSIONS: We conclude that the number
and incidence of fatal childhood injuries have decreased dramatically in
Finland between 1971 and 1995. The reasons for this positive development are
multifactorial, but improved traffic safety and trauma care are probably
very important. In children's serious non-fatal injuries the development has
not been so encouraging and therefore children's injury prevention should
receive continuous intense attention.
- Klassen TP; MacKay JM; Moher D; Walker A; Jones AL. Community-based injury prevention interventions. Future Child 2000 Spring-Summer;10(1):83-110.
ABSTRACT: Community-based interventions offer a promising solution for
reducing child and adolescent unintentional injuries. By focusing on
altering behavior, promoting environmental change within the community, or
passing and enforcing legislation, these interventions seek to change social
norms about acceptable safety behaviors. This article systematically reviews
32 studies that evaluated the impact of community-based injury prevention
efforts on childhood injuries, safety behaviors, and the adoption of safety
devices. Interventions targeted schools, municipalities, and cities. Most
relied on an educational approach, sometimes in combination with legislation
or subsidies, to reduce the cost of safety devices such as bicycle helmets.
Results indicate that community-based approaches are effective at increasing
some safety practices, such as bicycle helmet use and car seat use among
children. The evidence is less compelling that such interventions increase
child pedestrian safety, increase adolescent vehicle safety by reducing
drinking and driving behaviors, or reduce rates of several categories of
childhood injuries. Strong evidence supporting the effectiveness of
community-based interventions is lacking, in part because few studies used
randomized controlled designs or examined injury rates among children and
youths as outcome measures. Nonetheless, this review identifies common
elements of successful community-based approaches that should be replicated
in future studies. First, the use of multiple strategies grounded in a
theory of behavior change is critical. Second, to maximize success,
interventions should be integrated into the community and approaches should
be tailored to meet unique community needs. Third, community stakeholders
should be included in the development of community-based strategies. This
community involvement and ownership of the intervention increases the
likelihood of modeling and peer pressure, leading to widespread adoption of
a safety behavior. Finally, when possible, a randomized controlled design
should be used to maximize the trustworthiness of reported findings and aid
decisions about where to invest resources in community-based approaches to
injury prevention.
- DiGuiseppi C; Roberts IG. Individual-level injury prevention strategies in the clinical
setting. Future Child 2000 Spring-Summer;10(1):53-82
ABSTRACT: Health care providers have numerous opportunities to intervene
with parents and children to promote child safety practices that reduce
rates of unintentional injuries. These individual-level interventions may be
delivered in a variety of settings such as physician offices, clinics,
emergency departments, or hospitals. This article systematically reviews 22
randomized controlled trials (RCTs) that examined the impact of
interventions delivered in the clinical setting on child safety practices
and unintentional injuries. The results indicate that counseling and other
interventions in the clinical setting are effective at increasing the
adoption of some safety practices, but not others. Specifically, motor
vehicle restraint use, smoke alarm ownership, and maintenance of a safe hot
tap water temperature were more likely to be adopted following interventions
in the clinical setting. Clinical interventions were not proven effective at
increasing a variety of safety practices designed to protect young children
from injuries in the home, increasing bicycle helmet use, or reducing the
occurrence of childhood injuries, though few studies examined the latter two
outcomes. Clinical interventions were most effective when they combined an
array of health education and behavior change strategies such as counseling,
demonstrations, the provision of subsidized safety devices, and
reinforcement. The article concludes with implications for research and
practice.
- Grossman DC. The history of injury control and the epidemiology of child and
adolescent injuries. Future Child 2000 Spring-Summer;10(1):23-52.
ABSTRACT: Unintentional injuries claim the lives of more children each year
than any other cause of death. A substantial proportion of child
hospitalizations and emergency department visits also are attributable to
unintentional injuries. The conceptualization of unintentional injuries as a
public health problem that is preventable has gained credibility over the
past few decades, as effective solutions to reduce the burden of
injuries--such as child safety seats, bicycle helmets, and smoke
detectors--have been identified. Successful implementation of these
strategies requires a clear understanding of the circumstances surrounding
injuries and the risk and protective factors that influence the likelihood
that a child will be injured. Although adequate data on these factors is
available for some causes of injury, such as motor vehicle crashes, it is
almost nonexistent for others, such as unintentional firearm injuries.
Overall, unintentional injury rates are highest among adolescents ages 15 to
19, males, children from impoverished families, and minorities. Also, some
injuries occur more often in rural areas. Although these demographic risk
factors cannot be modified, environmental and behavioral risks, such as
unsafe roads, alcohol intoxication, unfenced swimming pools, and the absence
of a smoke detector in the home, can be modified successfully with
appropriate strategies. Motor vehicle occupant, drowning, and pedestrian
injuries were the most common unintentional injuries causing death among
children ages 0 to 19 in 1996. Together, these mechanisms accounted for more
than half of all unintentional injury deaths among children and adolescents,
although rates varied considerably by age. Child injury death rates across
most age categories and mechanisms of injury have declined during the past
20 years, yet the reasons for these declines are poorly understood.
Additional research about risk and protective factors, and efforts to
implement successful injury prevention strategies among populations at
highest risk for injuries, are necessary to further reduce the toll on
children's lives.
- Smith RJ 3rd; Dellapenna AJ Jr; Berger LR. Training injury control practitioners: the Indian Health Service model. Future Child 2000 Spring-Summer;10(1):175-88.
ABSTRACT: Many individuals practicing injury control have not received
specific training for their work, in large part because of a scarcity of
training opportunities. Consistent with its mission of "raising the health
status of American Indian and Alaska Native people to the highest possible
level," the Indian Health Service (IHS) created an innovative training
program for federal and tribal employees. The model emphasizes training that
is practical and can be applied immediately to community interventions. Many
features of the IHS training model have broad applicability to other
settings. These features include the use of experiential instruction,
preceptors, and community case studies to train individuals from diverse
cultural and educational backgrounds; educational strategies for employed
adults; and courses that promote community empowerment. The development of
IHS training courses are guided by community input, epidemiological data,
advances in knowledge, and program evaluations. Courses range from a
half-day "minicourse" to a full-year fellowship program. The success of the
training model is evident in programs instituted by IHS Injury Prevention
Specialist Fellowship graduates, whose projects have ranged from drowning
prevention in Alaska to fire safety in North Dakota. The IHS training model
could be applied in a variety of other community-based settings, but it is
most relevant to programs that train individuals from diverse backgrounds
who are not full-time students and programs that make community needs an
organizational priority.
- Miller TR; Romano EO; Spicer RS. The cost of childhood unintentional injuries and the value of
prevention. Future Child 2000 Spring-Summer;10(1):137-63.
ABSTRACT: Cost data are useful in comparing various health problems,
assessing risks, setting research priorities, and selecting interventions
that most efficiently reduce health burdens. Using analyses of national and
state data sets, this article presents data on the frequency, costs, and
quality-of-life losses associated with unintentional childhood injuries in
1996. The frequency, severity, potential for death and disability, and costs
of unintentional injury make it a leading childhood health problem.
Unintentional childhood injuries in 1996 resulted in an estimated $14
billion in lifetime medical spending, $1 billion in other resource costs,
and $66 billion in present and future work losses. These injuries imposed
quality-of-life losses equivalent to 92,400 child deaths. Since Medicaid and
other government sources paid for 39% of the days children spent in
hospitals due to unintentional injuries, the government has a financial
interest in, and arguably a responsibility for, assuring the safety of
disadvantaged children. Federal agencies, however, devote relatively few
public dollars to injury prevention research and programming. Several proven
child safety interventions cost less than the medical and other resource
costs they save. Thus, governments, managed care companies, and third-party
payers could save money by encouraging the routine use of selected child
safety measures such as child safety seats, bicycle helmets, and smoke
detectors. Yet, these and other proven injury prevention interventions are
not universally implemented.
- Schieber RA; Gilchrist J; Sleet DA. Legislative and regulatory strategies to reduce childhood
unintentional injuries. Future Child 2000 Spring-Summer;10(1):111-36.
ABSTRACT: Laws and regulations are among the most effective mechanisms for
getting large segments of the population to adopt safety behaviors. These
have been applied at both the state and federal levels for diverse injury
issues. Certain legal actions are taken to prevent the occurrence of an
otherwise injury-producing event, while other legal actions are designed to
prevent injury once an event has occurred. At the federal level, effective
laws and regulations have been directed at dangers posed by unsafe
manufactured products or motor vehicle design. At the state level, effective
safety laws and regulations have been directed at encouraging safety
behaviors and regulating the use of motor vehicles or other forms of
transportation. In this article, six legislative efforts are described to
point out pros and cons of the legislative approach to promoting safety.
Three such efforts are aimed at preventing injury-producing events from
occurring: mandating child-resistant packaging for prescription drugs and
other hazardous substances, regulating tap water temperature by presetting a
safe hot-water heater temperature at the factory, and graduated licensing.
Three other examples illustrate the value and complexities of laws designed
to prevent injuries once an injury-producing event does occur: mandatory
bicycle helmet use, sleep-wear standards, and child safety seat use. This
article concludes with specific recommendations, which include assessing the
value of laws and regulations, preventing the rescission of laws and
regulations known to work, refining existing laws to eliminate gaps in
coverage, developing regulations to adapt to changing technology, exploring
new legal means to encourage safe behavior, and increasing funding for basic
and applied research and community programs. Further reductions in childhood
injury rates will require that leaders working in the field of injury
prevention together provide the creativity to devise new safety devices and
programs, incentives to persuade the public to adopt a "culture of safety"
as a social norm, training and education to develop new leaders and workers,
and the political will to challenge the status quo and engage the public
interest.
- R J Lilford, David Braunholtz. Who's afraid Of Thomas Bayes? J Epidemiol Community Health 2000;54:731-739.
ABSTRACT:
Sometimes direct evidence is so strong that a prescription for practice is
decreed. Usually, things are not that simple leaving aside the possibility
that important trade offs may be involved, direct comparative data may be
imprecise (especially in crucial sub-groups) or subject to possible bias, or
there may be no direct comparative evidence; but still decisions have to be
made. In these circumstances, indirect evidence the plausibility of
effects enters the frame. But how should we describe the extent of
plausibility and, having done so, how can this be integrated with any direct
evidence that might exist. Also, how can allowance be made in a transparent
(that is, explicit) way for perceptions of the size of bias in the direct
evidence. Enter the Reverend Thomas Bayes; plausibility (however
derived laboratory experiment, qualitative study or just "experience") is
captured numerically as degrees of belief ("prior" to the direct data) and
updated (by the direct evidence) to yield "posterior" probabilities for use
in decision making. The mathematical model used for this purpose must
explicitly take account of assumptions about bias in the direct data. This
paradigm bridges theory and practice, and provides the intellectual scaffold
for those who recognize that (numerically definable) probabilities, and
values (also numerically definable) underlie decisions, but who also realize
that subjectivity is ineluctable in science.
See Part 2 for the categories
- Residential
- Sports and Recreation
- Suicide
- Violence and Weapons
- Work and Occupational Injuries
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