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PubMed2002

Intensive care units in Croatia: 2001 survey.

AIM: To establish a framework for the Intensive Care Units (ICU) Register in Croatia, and examine the relation between their present organization and medical practices and their outcome performances. METHODS: The survey of a total of 123 ICUs in Croatia was conducted between February 1 and October 31, 2001. Census questionnaires were filled out by ICU chiefs of staff. Demographic data, data on hospital and ICU structure and organization, disposable equipment, admission and discharge decision-making, outcome, and patient demographic data were collected for February 1, 2001. Descriptive statistics was used for data analysis. RESULTS: On February 1, 2001, there were 123 ICUs in Croatia. The questionnaire was filled out by 117 ICU chiefs of staff (95% response rate). The total number of ICUs beds was 900, comprising 3.3% of all hospital beds. Croatian ICUs were divided into 13 subtypes; 89% of them were adjoined to hospital departments of various subspecialties and only 13 (11%) were freestanding. The number of ICUs per hospital, number of ICU beds, quantity of disposable equipment, and number of permanently employed medical and nursing staff within hospitals and individual units increased as hospitals enlarged. Also, the number of mixed surgical/medical and coronary care/medical units decreased, and specialized units became prevalent. The mortality data in Croatian ICUs were similar to those reported elsewhere in the world: the lowest mortality was found in psychiatric ICUs (3%) and the highest in an ICU for infective diseases (30%), followed by neurological (19%), medical (17%), and respiratory (16%) ICUs. CONCLUSION: Establishing a database on intensive care medicine and assessing the performance of ICUs in Croatia could serve as a model for improvement of ICU service in other transition countries.

Croatia↗
PubMed2004

Does universal comprehensive insurance encourage unnecessary use? Evidence from Manitoba says "no".

BACKGROUND: Many argue that "free" medical care leads to unnecessary use of health resources. Evidence suggests that user fees do discourage physician use, at least by those of low socioeconomic status. In this study, we compare health care utilization and health among socioeconomic groups to determine whether people of low socioeconomic status see physicians more than would be expected given their health status. METHODS: We examined the use of health care services (physicians and hospitals) by residents of Winnipeg, Manitoba, in 1999. The cost of physician services was drawn directly from the claims filed, and the cost of hospital services was estimated using the Case Mix Group and Day Procedure Group methods linked to resource intensity weights and Manitoba hospital costs. We used neighbourhood indicators of socioeconomic status from the 1996 census and measured health status by examining rates of premature mortality, acute myocardial infarction, hip fracture (1995-1999) and diabetes (1999). Using these measures, we compared health status and health care use of residents living in areas with low average household incomes with those living in areas with high average household incomes. All rates were age- and sex-adjusted across the groups. RESULTS: The province spent 44% more providing hospital and physician services to residents of Winnipeg neighbourhoods with the lowest household incomes (820 dollars/person annually v. 596 dollars/person for residents of the neighbourhoods with highest household incomes). However, expenditures were strongly related to health status. The 70% of the population on which the province spends 10% of its health care dollars scored well on all health indicators, and the 10% of the population on which 74% of the dollars are spent scored poorly. In each expenditure group, those with lower socioeconomic status had poorer health. In the highest expenditure group, those with lowest socioeconomic status had 82% higher premature mortality rates (23.0 v. 12.6 per 100,000 population) and 53% higher hip fracture rates (5.5 v. 3.6 per 100,000 population) than those with the highest socioeconomic status. Despite their poorer health, in each expenditure group, residents of the neighbourhoods with the lowest household incomes incurred physician expenditures that were similar to those of residents of wealthier neighbourhoods. INTERPRETATION: Most people use little health care; high-cost users are a small group of very sick people drawn from all neighbourhoods and all income groups. People living in areas with low average household incomes use fewer physician services than might be expected, despite their poor health status.

Adolescent↗
PubMed2005

Varying evolution of the New Zealand lung cancer epidemic by ethnicity and socioeconomic position (1981-1999).

AIM: Tobacco use and resultant health effects have been described as an epidemic that progresses through the population. This paper aims to describe and explain trends in lung cancer mortality by ethnicity and socioeconomic position in New Zealand between 1981-1999. METHODS: Cohort studies of the entire New Zealand population for 1981-84, 1986-89, 1991-94, and 1996-99 (linking census and mortality datasets) allowed direct determination of trends in lung mortality by income and education. For ethnicity, we used unlinked census and mortality data--but with correction factors applied for undercounting of Maori and Pacific deaths. RESULTS: Lung cancer mortality decreased in males and increased in females over the time period studied. In males, socioeconomic inequality persisted despite a decline in mortality in all socioeconomic groups. In females, a disproportionate increase in the mortality of lower socioeconomic groups compared to higher socioeconomic groups resulted in an increase in inequality. Divergent trends by ethnic group resulted in an increase in ethnic inequalities between 1981 and 1996 in both males and females. CONCLUSIONS: There are significant and growing ethnic and socioeconomic inequalities in lung cancer mortality in New Zealand. In the current absence of concerted public health action these inequalities will probably widen in future decades.

Adult↗
PubMed2005

Chronic heart failure beyond city limits.

INTRODUCTION: Chronic heart failure (CHF) develops in frail elderly individuals who have suffered an acute or sustained insult to the structural efficiency of the heart due to the presence of underlying heart disease and/or hypertension. It is also more common in individuals with disproportionately high levels of cardiac disease or its risk factors, for example lower socioeconomic status. As such, this epidemic is particularly significant for older people, males and Aboriginal people; groups who comprise a greater proportion of the population in rural and remote Australia. The aim of this study is to determine if the rates of CHF differ between urban and rural Australia. METHOD: CHF prevalence rates derived from well validated international CHF prevalence data were applied to the Australian Bureau of Statistics Census data for 2001 and weighted to reflect the proportion of Aboriginal people in each geographical stratum. RESULTS: Australia wide, the estimated prevalence of CHF was 17.87 per 1000, ranging from 13.98/1000 in the Australian Capital Territory to 29.50/1000 in rural Northern Territory. Overall, CHF was more prevalent in rural and remote regions (19.84/1000) and large urban centres (19.01/1000) than in capital cities (16.94/1000) (p<0.001). High prevalence rates were also noted in the idyllic rural locations favoured by retirees. In Victoria, Western Australia, South Australia and the Australian Capital Territory over 70% of the estimated individual cases were located in capital cities. In New South Wales, Queensland, Tasmania and the Northern Territory the highest proportion of cases occurred outside capital cities. CONCLUSION: The main significance of these findings is that while a majority of heart failure may occur among people living in cities (because that is where most people live), a disproportionate number of cases occur among people living outside these cities (due to age and other socio-demographic risk factors) where services may be fewer and less accessible.

Adult↗
PubMed1991

The use of own-child checks to determine remarriage status.

The 1900 Federal Census of the United States did not ask currently-married women whether they had been married previously. This note uses the direct report on remarriage in the 1910 census to evaluate the performance of the "own-child checks" that several researchers have used with the 1900 census to substitute for direct information on remarriage. Accurate information on remarriage status is important for fertility and mortality estimation methods that rely on marital duration. The checks detect fewer than two-thirds of wives who report they are remarried. The use of these checks, however, does not introduce large amounts of error in an analysis of either fertility or mortality. The checks work better for white women than for black women.

Adolescent↗
PubMedDate not supplied

WIC program participation--a marketing approach.

Recent evaluation studies have described the benefits accruing to low-income women and children who participate in the Special Supplemental Food Program for Women, Infants, and Children (WIC). However, participation is not uniform among all groups of eligible persons. This study examines the geographic variation in WIC participation rates of eligible pregnant women in Rhode Island to determine whether the program is effective in reaching the neediest segments of the population. Eight groups of small geographic areas in Rhode Island (census tracts) were formed on the basis of need for maternal and child health services, as determined from a statistical method employing factor and cluster analysis of existing health and sociodemographic data. Among these eight groups, participation rates in WIC during 1983-84 ranged from 46 percent to more than 100 percent of estimated eligible pregnant women. The rates were positively correlated with measures of need, strongly (r = 0.92) with an index of maternal risk, and less strongly (r = 0.79) with an index of birth outcomes. The results of this study have enabled the Rhode Island WIC Program to direct its outreach efforts more specifically to geographic areas where the need for the program's assistance is greatest. The procedures described in this report comprise a technique that can be generally applied to measure program effectiveness in marketing and outreach where relevant data are available by small geographic areas. The data requirements are (a) population-based estimates of program need and (b) program utilization measures. If these data can be aggregated to a common set of small geographic areas, the use of marketing analysis techniques becomes possible, and program benefits in the area of outreach and recruitment can be realized.

Female↗
PubMed1993

[Health inequalities in Barcelona and Valencia].

BACKGROUND: Inequalities in health have been internationally recognized as an important public health problem with a reduction of 25% being the first target of WHO--Europe for the year 2000. It is, therefore, important to describe and monitor the same. METHODS: An ecological study was performed using secondary data from the statistics of mortality (years 1985-1988) and the municipal censuses from the year 1986 to describe and compare inequalities in health in the cities of Valencia and Barcelona with neighborhoods being the unit of observation and analysis. RESULTS: Although the rates of mortality in Barcelona city are slightly inferior and those of Valencia slightly higher to those of Spain, both cities demonstrate important inequalities in regard to mortality in their neighborhoods with respect to standardized mortality which ranged from 78 to 182 in Barcelona and from 63 to 147 in Valencia. The privileged zones in Barcelona are those of Pedralbes and Sant Gervasi and in Valencia in the neighborhoods of Sant Pau and Jaume Roig with the most unfavorable neighborhoods being District I in Barcelona (Gothic Quarter, City Park, Barceloneta and Raval) and the Na Rovella and Fuensanta neighborhoods of Valencia. The level of inequality in both cities is very similar. Statistically significant associations have been found in both cities between the state of health and the level of poverty in the neighborhoods according to an approximation to the Townsend et al indexes. CONCLUSIONS: The description of important inequalities in two large Spanish cities suggests the possibility of its existence in other cities and established the urgent need for a study using comparable methodologies. With the use of routine and presently available data sources it is possible to describe and posteriorly monitor the level of inequality in large cities in Spain. The development of policies to diminish the inequalities in the large cities would provide considerable gains in terms of human lives. The present results support the hypothesis that material conditions in everyday life play an important role as a condition for public health inequality.

Adolescent↗
PubMedDate not supplied

Ecologic proxies for household income: how well do they work for the analysis of health and health care utilization?

BACKGROUND: Researchers often use census-derived measures of socioeconomic status (SES) when personal information is not available. Theory predicts that the resulting misclassification will blunt associations between outcomes and SES and that control for confounding by SES will be less effective. The purpose of this paper was to examine the magnitude of this problem using data from the National Population Health Survey (NPHS). METHODS: Subjects were 4,037 respondents to the NPHS who were linked to the Ontario Health Insurance Plan. An ecologic measure of income was obtained by linkage of subjects' postal codes to the Census. RESULTS: The relationships between the ecologic-level measure and health outcomes or health services utilization were attenuated in comparison to the relationships relative to the direct measure of household income. The ecologic measure also produced poorer control for confounding by income in the analysis of other health relationships. CONCLUSIONS: Many interesting public health and health services questions can be addressed only with the use of ecologic level socioeconomic information. While most of the results were qualitatively similar when the direct and ecologic measures were compared, researchers and users of research findings should be aware that attenuated or potentially misleading findings may result from the use of these methods.

Female↗
PubMed2006

The implication of obesity on total antioxidant capacity in apparently healthy men and women: the ATTICA study.

BACKGROUND AND AIM: We evaluated the association of obesity with serum total antioxidant capacity (TAC), in a population-based sample of 3042 adults. METHODS AND RESULTS: During 2001-2002 we randomly enrolled 1514 men (18-87 years old) and 1528 women (18-89 years old), from the Attica area in Greece into the study, and the sample was stratified by the age-sex distribution of the region (census 2001). Among several variables we also measured serum TAC and weight, height, waist and hip circumferences. Waist circumference greater than 102 cm for men and 88 cm for women was considered an indicator of central fat. METHODS AND RESULTS: Mean waist circumference was 98+/-13 cm in men and 84+/-22 cm in women (P<0.001), while mean hip circumference was 106+/-28 cm in men and 103+/-13 cm in women (P<0.001). Central fat prevailed in 53% of men and 45% of women (P<0.001). Male participants with central fat exhibited 5% lower TAC concentrations compared to leaner individuals (214+/-35 vs. 226+/-33 micromol/L, P=0.04) and female participants with central fat exhibited 7% lower TAC concentrations (256+/-38 vs. 239+/-27 micromol/L, P=0.03). Similarly, obese or overweight male participants had 6% lower TAC concentrations compared to normal weight (217+/-33 vs. 234+/-39 micromol/L, P=0.03) and female obese or overweight participants had 10% lower TAC concentrations (226+/-32 vs. 250+/-30 micromol/L, P=0.02) compared to the others. CONCLUSIONS: Our results suggest an inverse relationship between body fat, central adiposity and antioxidant capacity, irrespective of age and various other potential confounders, namely smoking, physical activity, dietary habits, blood pressure, glucose levels, and lipid concentrations.

Abdominal Fat↗
PubMed2006

The role of socioeconomic status on hip fracture.

INTRODUCTION: The impact of socioeconomic status-income and acculturation-on hip fracture is not well understood. We studied 116,919 fractures among 8,144,469 people in California. Greater income and English fluency predict lower fracture incidence. Lower income and immigrant populations are at increased risk for hip fracture and require intervention. Race/ethnicity is a major determinant of hip fracture risk. Although socioeconomic status (e.g., income and acculturation) is often associated with race/ethnicity, its impact on hip fracture incidence is less well understood. METHODS: We carried out a retrospective, population-based, study of persons with hip fractures in California, 1996 to 2000, compared to census estimates by zip code. We performed Poisson regression analyses to calculate hip fracture incident rate ratios for gender, age, race/ethnicity, income, language (percent non-English speakers)-a proxy for acculturation-and living in rural areas. RESULTS: During the 5-year period, 116,919 fractures occurred among 8,144,469 persons (2.87 fractures/1,000 persons per year). Higher income predicted lower hip fracture incidence. Persons in the highest decile of estimated income had an incident rate ratio (IRR) of 0.79 (95% confidence interval (CI) 0.77 to 0.82) compared with those in the lowest decile. Greater IRR of hip fracture was predicted for persons living in areas with a greater percent of non-English speakers (IRR 1.004, 95% CI 1.003 to 1.005). CONCLUSIONS: Low income and language fluency are predictors of greater hip fracture incidence. Although much attention is given to the aging of the "baby boomers", low income and immigrant populations are at increased risk for hip fracture and require intervention.

Acculturation↗
PubMed2000

The bronchodilator effect of intravenous glucagon in asthma exacerbation: a randomized, controlled trial.

STUDY OBJECTIVE: Glucagon is a rapid-acting smooth muscle relaxant with a short half-life. Previous studies suggested glucagon may have bronchodilator effects. We sought to determine whether intravenous glucagon produces clinically important immediate bronchodilation in emergency department patients with asthma exacerbation. METHODS: We conducted a randomized, double-blind, placebo-controlled study at 2 university-affiliated community teaching hospital EDs (annual census 90,000). ED patients 18 to 50 years old with asthma exacerbation and peak expiratory flow rate (PEFR) less than 350 L/min were eligible. Exclusion criteria were need for intubation, chronic obstructive pulmonary disease, diabetes mellitus, insulinoma, pheochromocytoma, pregnancy, lactation, or current oral steroid treatment. Patients were randomly assigned to receive glucagon 0.03 mg/kg or an equivalent volume of saline solution intravenously. At 10 minutes, PEFR was measured and all patients began standardized albuterol therapy. Successful bronchodilation was a PEFR increase of 60 L/min at 10 minutes. RESULTS: Success occurred in 2 (9.5%) of 21 glucagon-treated patients and 3 (12%) of 25 placebo-treated patients (95% confidence interval [CI] for difference of -2.5% [-20.4% to 15. 4%]). Mean PEFR improvement for glucagon was 2 L/min versus 9 L/min for placebo (95% CI for difference of -7 L/min [-36 L/min to 23 L/min]). CONCLUSION: Glucagon alone provided no clinically important immediate bronchodilation in ED patients with asthma exacerbation.

Adult↗
PubMed1997

The structure of radiation oncology in the United States in 1994.

PURPOSE: 1) to measure the basic structural characteristics of radiation oncology facilities for the entire country, providing census data for January 1, 1994; 2) to allow comparisons by facility type, equipment, or patient load; 3) to allow comparisons of the patterns of equipment and personnel to previous surveys; and 4) to make a preliminary assessment of the geographic distribution of facilities. METHODS AND MATERIALS: A mail survey verified whether each potential facility delivered megavoltage radiation therapy and collected data on treatment machines, other equipment, personnel, new patients, and procedures performed. Responses were obtained from 99% of potential facilities. The census data was summarized for the entire country, by hospital-based, free-standing, or federal category, by single or multiple treatment machine group, and by new patient load category. Geographic analysis compared the center of radiation oncology facilities with the center of cities or towns having a population of more than 25,000 residents in 1990. RESULTS: In the United States in 1994, 1542 facilities delivered megavoltage radiation therapy, with 2744 treatment machines, 2777 FTE radiation oncologists, 1349 FTE physicists, 1314 FTE dosimetrists, and 7167 FTE radiation therapists. They treated 560,262 new patients and reported that 60% were treated with curative intent. Eighty percent of the facilities had a dedicated treatment planning computer and 15% had a time-sharing treatment-planning computer, but 5% had no treatment-planning capability. Ninety-five percent of all facilities reported that patients were simulated at that facility. Fourteen percent of all facilities used hyperthermia, 8% intraoperative radiation therapy, 12% stereotactic radiosurgery, and 19% conformal therapy with 3D planning. Of all facilities 35% reported having a dedicated CT scanner and 12% reported having a CT simulator in the department. The distributions of these measures were reported for hospital-based, free-standing, and federal facilities, for single-treatment machine, and multiple-treatment machines facilities, and for three categories based on patient load. Only 18 cities with a population over 25,000 were more than 25 miles from a radiation oncology facility, of which only eight were more than 50 miles from a facility. CONCLUSION: The Facilities Surveys continue to provide a unique source of census data on radiation oncology in the United States, allowing comparisons by facility group and over time.

Facility Design and Construction↗
PubMed1991

Increasing brain cancer rates in Canada.

OBJECTIVE: To analyse brain cancer patterns in Canada, particularly according to age and sex distributions, temporal patterns and regional variations. Changes in diagnostic techniques, survival rates and trends by tumour type were also examined. DESIGN: Descriptive epidemiologic study based on Canada-wide population data for 1959-88. OUTCOME MEASURES: Rates of death, incidence and admission to hospital because of brain cancer, as well as survival time and methods of diagnosis. SUBJECTS: Incidence and death rates and time trends were examined for Canada as a whole, by province and by census division. RESULTS: The rates of death from brain cancer increased rapidly among Canadians aged 55 years or more from 1959 to 1988. In particular, age-adjusted death rates increased by 117%, 797% and 118% among men 65 to 74 years, 75 to 84 and 85 or more respectively. The corresponding increases among women were 138%, 535% and 400%. The incidence rates also increased substantially. The trends in incidence rates by tumour type indicated that the increase was more pronounced for glioblastomas. The incidence rates of cases detected histologically, radiologically and clinically all increased. CONCLUSIONS: Because glioblastomas are generally easier to diagnose than astrocytomas and because the incidence rates of glioblastomas were found to increase substantially, the increased brain cancer rates among elderly people may not be entirely attributable to improved diagnostic techniques. However, analytic investigations of the impact of changes in diagnostic procedures on brain cancer trends are needed to clarify this issue.

Adolescent↗
PubMedDate not supplied

On the application of the ICIDH and ICF in developing countries: evidence from the United Nations Disability Statistics Database (DISTAT).

The paper reviews the application of the ICIDH and the ICF in developing countries using data and information available in the United Nations Disability Statistics Database at the United Nations Statistics Division. The focus of the paper is limited to studies carried out in the 1990s and also censuses conducted in the 2000 round of censuses. There are substantial variations between studies in the questions used to identify the population with disabilities, and for most countries, these questions are not based on either the ICIDH or the ICF. Disability status is ascertained mainly through use of impairment screens that include a list of a few severe impairments. Recent studies show use of the ICIDH and also the ICF in the development of questions on disability. This may be attributed mainly to guidelines in the United Nations census recommendations regarding use of the ICIDH framework and terminology to develop the question(s) on disability. Work of the United Nations Statistics Division aimed at improving the international comparability of methods and use of international standards could increase use of the ICF in disability measurement. This includes regional training workshops and also the work of the newly created Washington City Group on Disability Measurement.

Activities of Daily Living↗
PubMed2006

[Selection of risk and diagnosis in diabetic polyneuropathy. Validation of method of new systems].

INTRODUCTION: In a previous study we developed a specific algorithm, the polyneuropathy selection method (PSM) with 4 parameters (age, HDL-C, HbA1c, and retinopathy), to select patients at risk of diabetic polyneuropathy (DPN). We also developed a simplified method for DPN diagnosis: outpatient polyneuropathy diagnosis (OPD), with 4 variables (symptoms and 3 objective tests). OBJECTIVES: To confirm the validity of conventional tests for DPN diagnosis; to validate the discriminatory power of the PSM and the diagnostic value of OPD by evaluating their relationship to electrodiagnosis studies and objective clinical neurological assessment; and to evaluate the correlation of DPN and pro-inflammatory status. DESIGN: Cross-sectional, crossed association for PSM validation. Paired samples for OPD validation. SETTING: Primary care in 3 counties. PARTICIPANTS: Random sample of 75 subjects from the type-2 diabetes census for PSM evaluation. Thirty DPN patients and 30 non-DPN patients (from 2 DM2 sub-groups in our earlier study) for OPD evaluation. METHODS: The gold standard for DPN diagnosis will be studied by means of a clinical neurological study (symptoms, physical examination, and sensitivity tests) and electrodiagnosis studies (sensitivity and motor EMG). Risks of neuropathy, macroangiopathy and pro-inflammatory status (PCR, TNF soluble fraction and total TGF-beta1) will be studied in every subject. EXPECTED RESULTS: Electrodiagnosis studies should confirm the validity of conventional tests for DPN diagnosis. PSM and OPD will be valid methods for selecting patients at risk and diagnosing DPN. There will be a significant relationship between DPN and pro-inflammatory tests.

Algorithms↗
PubMed2000

Neighborhood poverty as a predictor of intimate partner violence among White, Black, and Hispanic couples in the United States: a multilevel analysis.

PURPOSE: This study assessed the contribution of neighborhood poverty, measured at the census tract level, to the risk of male-to-female and female-to-male partner violence (MFPV, FMPV) among white, black, and Hispanic couples in the United States. METHODS: As part of the 1995 National Alcohol Survey, a representative sample of married/cohabiting couples was obtained through a multistage, multicluster household probability sampling frame. The outcome variables, MFPV and FMPV, were measured through the Conflict Tactics Scale, Form R. Sociodemographic, psychosocial, and alcohol consumption covariates that were statistically significant through bivariate analysis were retained as individual-level predictors. Neighborhood poverty, indicating residence in a census tract where greater than 20% of the population lived below the Federal poverty line, was assessed by appending 1990 Census data to the primary data set. Multilevel logistic regression models were constructed, with separate analyses performed for each outcome (MFPV, FMPV) among the white, black, and Hispanic couples. RESULTS: Couples residing in impoverished neighborhoods are at increased risk for both MFPV and FMPV. The association between residence in an impoverished neighborhood and MFPV was statistically significant for black couples (Odds Ratio [OR] 2.87; 95% Confidence Interval [CI] 1.36, 6.07). The association between residence in an impoverished neighborhood and FMPV was statistically significant for black couples and white couples. CONCLUSIONS: Characteristics of the socioenvironment, such as neighborhood poverty, are associated with the risk of partner violence, particularly among black couples. Policies aimed at reducing community poverty may contribute to effective partner violence prevention strategies.

Black or African American↗
PubMed1977

A method for analysing fertility of heterozygotes for autosomal recessive disorders, with special reference to cystic fibrosis, Tay-Sachs disease and phenylketonuria.

Increased fertility of heterozygotes with respect to decreased foetal loss among offspring of heterozygotes has been proposed by several authors as a possible explanation for the high gene frequency of CF, TSD and PKU in certain populations. Studies comparing reproductive outcome of heterozygotes with reproductive performance in the general population or in special control groups have been done on several occasions. These studies, however, are known to be heavily biased, on the one side by the fact that ascertainment of heterozygotes through affected offspinrg will tend to underestimate the relative frequency of smaller families, and on the other side because of the inadequacy of census data for comparison and the biases inherent in selection of control families. Careful analysis of the biases involved provides suggestions for proper corrections. From this a method has been developed which offers a better approach to the study of heterozygote fertility in those autosomal recessive conditions which lack a test for direct heterozygote detection.

Cystic Fibrosis↗