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PubMedDate not supplied

Applying sample survey methods to clinical trials data.

This paper outlines the utility of statistical methods for sample surveys in analysing clinical trials data. Sample survey statisticians face a variety of complex data analysis issues deriving from the use of multi-stage probability sampling from finite populations. One such issue is that of clustering of observations at the various stages of sampling. Survey data analysis approaches developed to accommodate clustering in the sample design have more general application to clinical studies in which repeated measures structures are encountered. Situations where these methods are of interest include multi-visit studies where responses are observed at two or more time points for each patient, multi-period cross-over studies, and epidemiological studies for repeated occurrences of adverse events or illnesses. We describe statistical procedures for fitting multiple regression models to sample survey data that are more effective for repeated measures studies with complicated data structures than the more traditional approaches of multivariate repeated measures analysis. In this setting, one can specify a primary sampling unit within which repeated measures have intraclass correlation. This intraclass correlation is taken into account by sample survey regression methods through robust estimates of the standard errors of the regression coefficients. Regression estimates are obtained from model fitting estimation equations which ignore the correlation structure of the data (that is, computing procedures which assume that all observational units are independent or are from simple random samples). The analytic approach is straightforward to apply with logistic models for dichotomous data, proportional odds models for ordinal data, and linear models for continuously scaled data, and results are interpretable in terms of population average parameters. Through the features summarized here, the sample survey regression methods have many similarities to the broader family of methods based on generalized estimating equations (GEE). Sample survey methods for the analysis of time-to-event data have more recently been developed and implemented in the context of finite probability sampling. Given the importance of survival endpoints in late phase studies for drug development, these methods have clear utility in the area of clinical trials data analysis. A brief overview of methods for sample survey data analysis is first provided, followed by motivation for applying these methods to clinical trials data. Examples drawn from three clinical studies are provided to illustrate survey methods for logistic regression, proportional odds regression and proportional hazards regression. Potential problems with the proposed methods and ways of addressing them are discussed.

Clinical Trials as Topic↗
PubMed1994

HIV testing, HIV infection and associated risk factors among inmates in south-eastern French prisons.

OBJECTIVES: To estimate HIV seroprevalence in the two main remand and short-stay prisons of south-eastern France and to gather linked anonymous risk-factor information. SETTING: Baumettes prison, Marseille, France between 16 November and 21 December 1992. PARTICIPANTS: Using a self-administered questionnaire about HIV testing and risk factors for HIV infection, 295 male and 137 female inmates were interviewed. The response rate was 96% (100 and 90% for men and women, respectively). At the same time, 279 of a total of 432 (65%) inmates were serologically tested for HIV; 153 (35%) declined to provide a blood sample. DESIGN: Anonymous cross-sectional and surveillance survey. RESULTS: Twenty per cent of participants (84 our of 432) were intravenous drug (heroin) users (IVDU), 51% of whom reported needle-sharing prior to incarceration; 23% reported more than two sexual partners during the last year, and 13% sexual intercourse with an IVDU during the last 5 years. HIV status was available for 356 inmates (82%; 65% from blood samples and 17% from the questionnaire); 39 were HIV-infected (10.9%; 95% confidence interval, 7.7-14.2). The inmates not tested for HIV reported proportionally less risky behaviours than non-HIV-infected inmates. HIV seroprevalence was significantly higher among recidivist inmates (19.9 versus 4.4%; P < 0.0001). The rate of HIV infection was particularly high among IVDU (34 out of 84; 40%). More female non-IVDU were HIV-infected than male non-IVDU (4.1 versus 0.6%; P = 0.04). CONCLUSIONS: This study demonstrates the high prevalence of HIV infection in south-eastern French prisons, especially among IVDU. The rates may be related to the high prevalence of risky drug practices and to delays in the development of HIV prevention programmes for IVDU in France. The higher seroprevalence rate among recidivist inmates might be the result of risk behaviours during imprisonment. Another hypothesis is that recidivist inmates are at greater risk of HIV infection because of higher levels of drug use.

AIDS Serodiagnosis↗
PubMed1991

[Risk of Mycobacterium tuberculosis infection in Jalisco, Mexico].

Using a modified cluster sample design, skin tests with two TU PPD were performed on 4,083 first-grade children (mean age 6,7 years) in the state of Jalisco, Mexico, to estimate the annual risk of infection from Mycobacterium tuberculosis. The proportion of PPD reactions (a diameter of 10 mm or more of induration) was 7.6% in the Guadalajara metropolitan area and 5.5% in the rest of Jalisco. In the total sample, the proportion was 7.4% among children with scars attributed to BCG vaccine and 4.5% in children without BCG scars. The weighted proportion of children with PPD reactions of 10 mm or more was 6.8% statewide. The average annual risk of infection estimated from the group that had not received BCG vaccine was 0.82%. The results suggest that the incidence of smear-positive pulmonary tuberculosis is almost 10 times greater than the number of cases registered annually in Jalisco.

BCG Vaccine↗
PubMed1988

Age retirement in women. I. General presentation.

Within the framework of a longitudinal population study of age retirement in women, the short-term consequences of retirement were studied in 116 municipally employed women in the city of Malmö (230,000 inhabitants) in southern Sweden half a year before and half a year after retirement. The women represented about 40 different occupations, mostly within the sectors of health care, social services and administration. The study comprised four main parts, namely health and discomfort, social psychology, dietary habits and body composition, and oral health. The present paper concerns a general presentation of the study including sampling procedures and analyses of non-response. The response rate was a little more than 70%. Only a few significant differences were observed between non-responders and responders, such as more working hours per week, and more frequently a negative attitude towards retirement in the non-responders after retirement. This longitudinal prospective study of the same cohort of women has so far shown that the general design, sampling procedure and general methods of data collection appear adequate and feasible. In general, the study population was representative of women about to retire from municipal employment in Sweden. Results from the different studies will be presented elsewhere. To illustrate not only the short-term effects of retirement we intend to reexamine the same women about 2 years after the retirement.

Dental Health Surveys↗
PubMed2004

Clinical calibration of DSM-IV diagnoses in the World Mental Health (WMH) version of the World Health Organization (WHO) Composite International Diagnostic Interview (WMHCIDI).

An overview is presented of the rationale, design, and analysis plan for the WMH-CIDI clinical calibration studies. As no clinical gold standard assessment is available for the DSM-IV disorders assessed in the WMH-CIDI, we adopted the goal of calibration rather than validation; that is, we asked whether WMH-CIDI diagnoses are 'consistent' with diagnoses based on a state-of-the-art clinical research diagnostic interview (SCID; Structured Clinical Interview for DSM-IV) rather than whether they are 'correct'. Consistency is evaluated both at the aggregate level (consistency of WMH-CIDI and SCID prevalence estimates) and at the individual level (consistency of WMH-CIDI and SCID diagnostic classifications). Although conventional statistics (sensitivity, specificity, Cohen's kappa) are used to describe diagnostic consistency, an argument is made for considering the area under the receiver operator curve (AUC) to be a more useful general-purpose measure of consistency. In addition, more detailed analyses are used to evaluate consistency on a substantive level. These analyses begin by estimating prediction equations in a clinical calibration subsample, with WMH-CIDI symptom-level data used to predict SCID diagnoses, and using the coefficients from these equations to assign predicted probabilities of SCID diagnoses to each respondent in the remainder of the sample. Substantive analyses then investigate whether estimates of prevalence and associations when based on WMH-CIDI diagnoses are consistent with those based on predicted SCID diagnoses. Multiple imputation is used to adjust estimated standard errors for the imprecision introduced by SCID diagnoses being imputed under a model rather than measured directly. A brief illustration of this approach is presented in comparing the precision of SCID and predicted SCID estimates of prevalence and correlates under varying sample designs.

Adult↗
PubMed1997

Drug monitoring studies as a method of analyzing response criteria.

Two multicenter drug monitoring studies are presented. Some methodological problems are dealt with and the validity of such studies is discussed in terms of differential indication. In a first study (Lehmann et al., 1993) the results of a 12-week xanthinol niacinate treatment (500 to 3000 mg daily) in a cohort of 10,134 outpatients suffering from cerebrovascular insufficiencies were recorded systematically by nonreactive evaluation methods. The therapy was found to be most successful in patients with the target symptoms vertigo, tiredness, lack of concentration, affective disorder, and disturbances of vigilance and vitality. The most frequent side-effects were flush or heat sensations in 9.1% of the patients and gastrointestinal complaints in 3.3%. In a second study (Klieser et al., 1994) we systematically collected data from 219 patients with Major Depressive Disorder during five weeks of treatment with fluoxetine (20 mg daily). The results showed that depressively inhibited, anxious patients with a depression of minor severity, who showed a relatively marked improvement within the first week of treatment, profited the most from this therapy. The first study was designed to use nonreactive evaluation methods. Correlation analyses helped to identify the types of patient with a good response to treatment. The second study was organized on the model of conventional controlled pharmacological studies with the application of commonly used scales. The differential indication was to be inferred from the uni- and multivariate comparison of responders and nonresponders. In the light of these two studies, the problems of target definition, sample design, target variables, practicability, statistical analysis, and validity are discussed.

Adolescent↗
PubMed2002

Population pharmacokinetics model and limited sampling strategy for intravenous vinorelbine derived from phase I clinical trials.

AIMS: a) To characterize the pharmacokinetics of intravenous vinorelbine, b) to use a population analysis for the identification of patient covariates that might appreciably influence its disposition and c) to define a limited sampling strategy for further Bayesian estimation of individual pharmacokinetic parameters. METHODS: All data were collected from 64 patients (99 courses) entered in three different phase I trials that have been previously reported. All patients received vinorelbine as a 20 min infusion with dose levels ranging from 20-45 mg m-2. The population pharmacokinetic model was built in a sequential manner on a subset of two-thirds of the data, starting with a covariate-free model then progressing to a covariate model using the nonlinear-mixed effect methodology. The remaining one-third of the data were used to validate several sparse sampling designs. RESULTS: A linear three-compartment model characterized vinorelbine blood concentrations (n=1228). Two primary pharmacokinetic parameters (total clearance and volume of distribution) were related to various combinations of covariates. The relationship for total clearance (CLtotal (l h-1)=29.2xBSAx(1-0.0090 Plt)+6.7xWt/Crs) was dependent on the patient's body surface area (BSA), weight (Wt), serum creatinine (Crs) and platelet count before administration (Plt). The optimal limited sampling strategy consisted of a combination of three measured blood concentrations; the first immediately before the end of infusion or 20 min later, the second at either 1 h, 3 h or 6 h and the third at 24 h after drug administration. CONCLUSIONS: A population pharmacokinetic model and a limited sampling strategy for intravenous vinorelbine have been developed. This is the first population analysis performed on the basis of a large phase I database that has identified clinical covariates influencing the disposition of i.v. vinorelbine. The model can be used to obtain accurate Bayesian estimates of pharmacokinetic parameters in situations where extensive pharmacokinetic sampling is not feasable.

Adult↗
PubMed2001

Application and interpretation of simple odds ratios in physical therapy-related research.

Over the past several decades, physical therapists have demonstrated an increasing responsiveness to the profession's obligation to generate objective evidence for examination and intervention strategies employed in physical therapy practice. This trend is evident, not only in the increasing number of journals that are publishing physical therapy research, but in the growing sophistication of research design and analytic options used by investigators. At the same time, physical therapists are held increasingly accountable for adopting an evidence-based approach to practice. The result for many of us is a growing concern about our ability to interpret study findings. The ability to independently weigh the importance to our own practice of evidence reported in a study requires that we understand the strengths and potential weaknesses of the sample, design, and analyses being used. The odds ratio (OR) is one of the analytic measures that has only recently appeared in the physical therapy literature. Because the OR may be unfamiliar to physical therapists, the goal of this paper is to provide a description of the simple OR and a discussion of its uses, interpretation, and potential limitations.

Confidence Intervals↗
PubMed2005

[Method and design of the Telephone Health Survey 2003].

Telephone surveys are increasingly being used in public health research, also in Germany. In 2003 the Robert Koch Institute completed the first nationwide telephone survey predominantly on conditions and prevalence of selected chronic diseases (GSTel03). Its findings are presented in this publication. The tasks of planning, implementation and realization of procedures used in telephone surveys differ in many aspects from other modes of data collection. This article deals with the most important methodological aspects that were implemented and used in the course of the GSTel03 to ensure a high level of data quality. These include sample design, questionnaire development and the process of data collection (including the recruitment and training of the staff). Finally steps of data preparation for analysis including weighting procedures are described and calculation of contact and cooperation rates are reported.

Data Interpretation, Statistical↗
PubMed2001

Dietary soy isoflavone intake in older Japanese American women.

OBJECTIVE: In a sample of older Japanese American women, we aimed to: (1) describe the most commonly consumed soy foods, (2) estimate dietary soy isoflavone intake, (3) describe characteristics associated with dietary soy isoflavone intake, and (4) compare our estimates with previously published estimates in other Japanese samples. DESIGN: A 14-item soy food-frequency questionnaire was administered to older Japanese American women and responses were converted to quantitative estimates of soy isoflavones (genistein plus daidzein). Multiple regression was used to examine characteristics associated with dietary soy isoflavone intake, including self-reported lifestyle and cultural factors and dietary intake of various foods ascertained from a semi-quantitative food-frequency questionnaire. To compare our estimates with other samples, a review of the literature was conducted. SETTING/SUBJECTS: Data are from 274 women aged 65+ years, recruited from a longitudinal cohort study of Japanese Americans in King County, Washington State. RESULTS: The soy foods most commonly consumed were tofu (soybean curd), miso (fermented soybean paste) and aburaage (fried thin soybean curd). The mean intake of dietary soy isoflavones was 10.2 (standard deviation (SD), 12.4) mg day(-1), approximately a quarter to a half that of previously published estimates in Japanese samples. Dietary soy isoflavone intake was positively associated with speaking Japanese, the consumption of traditional Japanese dishes (kamaboko, manju and mochi), low-fat/non-fat milk and yellow/red vegetables, vitamin E supplement use, and walking several blocks each day. Dietary soy isoflavone intake was negatively associated with the consumption of butter. CONCLUSIONS: The estimated dietary soy isoflavone intake in Japanese American women living in King County, Washington State was about a quarter to a half that of women living in Japan. Dietary soy isoflavone intake was associated with speaking Japanese and healthy lifestyle and dietary habits.

Aged↗
PubMed2004

Skeletal muscle relaxant use in the United States: data from the Third National Health and Nutrition Examination Survey (NHANES III).

STUDY DESIGN: Population-based cross-sectional prevalence survey. OBJECTIVES: To define muscle relaxant use patterns in the United States. SUMMARY OF BACKGROUND DATA: Despite a long history of use for back pain and musculoskeletal disorders, national prevalence patterns of prescription muscle relaxant use have not been defined. METHODS: NHANES III (1988-1994) is an in-person health examination survey of the U.S. civilian population, based on a complex, multistage probability sample design. RESULTS: An estimated 2 million American adults reported muscle relaxant use (1-month period prevalence 1.0%; 95% confidence interval 0.8-1.3%). While virtually all (94%) used individual muscle relaxants rather than fixed combination muscle relaxant analgesics, two thirds took an additional prescription analgesic. Men and women had similar usage. Median user age was 42 years, but 16% of users were older than 60 years. Eighty-five percent of users took muscle relaxants for back pain or muscle disorders. Two thirds of muscle relaxant users had histories of recent back pain; however, only 4% of all those with a recent history of back pain reported any muscle relaxant use. Mean length of use was 2.1 years (95% confidence interval 1.6-2.6), with 44.5% taking medication longer than a year (95% confidence interval 35.7-53.3). Muscle relaxant use in the elderly, among older persons with ambulatory impairments, and in chronic obstructive pulmonary disease appeared undiminished compared with general population use. CONCLUSIONS: Although typically recommended for short-term treatment of back pain, muscle relaxants are often used chronically and are prescribed to subpopulations potentially at risk for adverse effects.

Adolescent↗
PubMed2006

Mathematics beliefs and achievement of elementary school students in Japan and the United States: results from the Third International Mathematics and Science Study.

Student self-beliefs are significantly related to several types of academic achievement. In addition, results from international assessments have indicated that students in Japan have typically scored above international averages (D. L. Kelly, I. V. S. Mullis, & M. O. Martin, 2000). In this study, the author examined relationships between mathematics beliefs and achievement of elementary school-aged students in the United States and Japan. The students had participated in the Third International Mathematics and Science Study (TIMSS; A. E. Beaton et al., 1996). The author examined several self-beliefs and used variance estimation techniques for complex sampling designs. The author identified a number of significant relationships between self-beliefs and mathematics achievement. Students who attributed success in mathematics to controllable factors (e.g., hard work, studying at home) showed higher test scores whereas students who attributed success in mathematics at school to external factors (e.g., good luck) tended to earn lower mathematics test scores. These results extend the findings of previous research results because the author examined large national samples of students in cross-cultural settings as part of a comprehensive international assessment.

Attitude↗
PubMedDate not supplied

The Outcomes Research in Nursing Administration Project: methodological issues in implementation.

This article describes the Outcomes Research in Nursing Administration (ORNA) project--a longitudinal, multisite study investigating the interrelationships of various hospital-level and nursing-unit-level characteristics, nursing unit organizational structure, and administrative and patient outcomes. A variety of methodological challenges were encountered in the actual conduct of the project in relation to the design, sampling plan, management of attrition, and data collection. The article describes these challenges and how they were successfully resolved.

Data Collection↗
PubMed2001

Serum retinyl esters are not associated with biochemical markers of liver dysfunction in adult participants in the third National Health and Nutrition Examination Survey (NHANES III), 1988--1994.

BACKGROUND: Serum retinyl ester concentrations are elevated in hypervitaminosis A. It was suggested that retinyl esters >10% of total serum vitamin A indicate potential hypervitaminosis, but this cutoff was derived from small clinical samples that may not be representative of the general population. OBJECTIVE: We sought to examine the distribution of serum retinyl ester concentrations and associations between retinyl ester concentrations and biochemical markers of liver dysfunction in a nationally representative sample. DESIGN: We assessed the associations between serum retinyl ester concentrations and 5 biochemical indexes of liver dysfunction by using multivariate linear and multiple logistic regression techniques and controlling for age, sex, use of supplements containing vitamin A, alcohol consumption, smoking status, and use of exogenous estrogens in 6547 adults aged > or =18 y in the third National Health and Nutrition Examination Survey (NHANES III), 1988--1994. RESULTS: Thirty-seven percent of the sample had serum retinyl ester concentrations >10% of total serum vitamin A and 10% of the sample had serum retinyl esters >15% of total vitamin A. We found no associations between serum retinyl ester concentrations and 1) concentrations of any biochemical variable (multiple linear regression) or 2) risk of having biochemical variables above the reference range (multiple logistic regression). We did not find a serum retinyl ester value with statistically significant sensitivity and specificity for predicting increases in biochemical indexes of liver dysfunction. CONCLUSIONS: The prevalence of serum retinyl ester concentrations >10% of the total vitamin A concentration in the NHANES III sample was substantially higher than expected but elevated retinyl ester concentrations were not associated with abnormal liver function.

Adult↗
PubMed2006

Prevalence, spectrum, and functional characterization of melanocortin-4 receptor gene mutations in a representative population-based sample and obese adults from Germany.

CONTEXT: Autosomal dominant inheritance of mutations in the melanocortin-4 receptor gene (MC4R) is currently regarded as the most relevant genetic cause for extreme obesity and affects 2-4% of extremely obese individuals. OBJECTIVE: Our objective was to assess the relevance of MC4R mutations in a German population-based sample. DESIGN AND SETTING: We conducted a mutation screen of the MC4R gene by capillary electrophoresis-based single-strand conformation polymorphism analysis and denaturing HPLC. PARTICIPANTS: Subjects included 4068 individuals of a German population-based study group [Kooperative Gesundheitsforschung im Raum Augsburg, Survey 4 (KORA-S4); i.e. Cooperative Health Research in the Region of Augsburg] and 1003 German obese adults (body mass index >or= 30 kg/m(2)). MAIN OUTCOME MEASURES: Samples with aberrant capillary electrophoresis-based single-strand conformation polymorphism analysis/denaturing HPLC patterns were resequenced. Functional studies including agonistic receptor stimulation (Nle-D-Phe-alpha-, alpha-, and beta-MSH) and cell surface expression assays were performed. RESULTS: Sixteen (six novel) coding nonsynonymous mutations were detected in 27 heterozygous individuals of KORA-S4. Four of the mutation alleles led to impaired receptor function in vitro; however, none of these six heterozygous mutation carriers was obese (body mass index >or= 30 kg/m(2)). In the obese adults, six coding nonsynonymous and a nonsense mutation were detected in 13 individuals. Only the nonsense mutation allele entailed impaired receptor function. CONCLUSIONS: Our study depicts prevalence, spectrum, and functional characterization of MC4R mutations in the German population-based sample KORA-S4. In this epidemiological study group, individuals heterozygous for nonsynonymous MC4R mutation alleles entailing impaired function were not obese. Furthermore, nonsynonymous MC4R mutations causing impaired receptor function were rare in German obese adults (two in 1003 = 0.2%).

Adult↗
PubMed1997

Planning and implementing a research project: Part 2.

This article is the second in a series of three focused on steps in the development of a research proposal. This second article presents the steps of research design, sampling, data collection procedures, and types of data collection instruments. The discussion of the steps focuses the reader on helpful hints pertinent to each step. Additional references are provided for a more detailed discussion of the process.

Data Collection↗
PubMed2002

Visual acuity and quality of life outcomes in cataract surgery patients in Hong Kong.

BACKGROUND: Visual acuity, visual functioning, and vision related quality of life outcomes after cataract surgery were assessed in a population based study in a suburban area of Hong Kong. METHODS: A cluster sampling design was used to select apartment buildings within housing estates for enumeration. All enumerated residents 60 years of age or over were invited for an eye examination and visual acuity measurement at a site within each estate. Visual functioning (VF) and vision related quality of life (QOL) questionnaires were administered to interview subjects who had undergone cataract surgery and to unoperated people with presenting visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity. RESULTS: 36.6% of the 310 cataract operated individuals had presenting visual acuity 6/18 or better in both eyes, and 40.0% when measured by pinhole. 4.5% were blind, with presenting visual acuity less than 6/60 in both eyes. Of operated eyes, 59.6% presented with visual acuity 6/18 or better. 11.2% of the operated eyes were blind with vision less than 6/60. Visual acuity outcomes 6/18 or better were marginally associated with surgery in private versus public hospitals. Lens status (pseudophakic versus aphakic) and surgical period (within the most recent 3 years versus before) were not significantly related to vision outcomes. Mean VF and QOL scores decreased consistently with decreasing vision status. Spearman correlation with vision status was 0.420 for VF scores and 0.313 for QOL scores. Among VF/QOL subscales, correlation was strongest for visual perception (r = 0.447) among VF subscales and weakest for self care (r = 0.171) among QOL subscales. Regression adjusted VF and QOL total scores for cataract operated individuals were slightly lower than for those of visually comparable unoperated individuals (p<0.05). CONCLUSIONS: Cataract operations in Hong Kong did not consistently produce good presenting visual acuity outcomes, suggesting that postoperative monitoring would be useful to minimise visual impairment in this population. Although vision outcomes were consistently correlated with all VF/QOL subscale scores, there was a differential impact with VF subscales usually being affected more by reduced acuity than the more general QOL subscales.

Aged↗
PubMed1994

Heparinized saline versus normal saline in maintaining patency of the radial artery catheter.

OBJECTIVE: To compare the ability of normal versus heparinized saline infusion to maintain patency of the radial artery catheter used for monitoring or multiple blood sampling. DESIGN: Randomized double-blind trial. SETTING: A university-affiliated hospital. PATIENTS: All 108 patients admitted to the surgical intensive care unit who required radial arterial line catheters. Excluded were patients who required emergency admission, those who refused to give consent, those who needed anticoagulants, thrombolytic or platelet therapy, those whose cannulation site was other than the radial artery, inadvertent discontinuation of the arterial line or incomplete data collection. This resulted in a sample of 78 adults, randomized according to date of admission. INTERVENTIONS: Forty patients admitted on odd-numbered dates received heparinized normal saline (2 units/mL), and 38 patients admitted on even dates received normal saline, both as continuous flush solutions. MAIN OUTCOME MEASURES: Measurement of radial artery flow and pressure before and after cannulation, and catheter patency during cannulation. RESULTS: The type of flush solution did not adversely affect the radial artery or the hand in any measurable way. Catheter blockage occurred in three patients receiving heparinized saline and seven patients receiving normal saline as the flush solution (p = 0.06). At 96 hours of cannulation, 92% of the catheters in the heparinized saline group were patent compared with 74% in the normal saline group. Intra-arterial blood pressure was inaccurate compared with the brachial cuff pressure in 6 patients in the heparinized saline group compared with 14 patients in the normal saline group (p < 0.03). CONCLUSIONS: There is no significant difference between flushing with normal saline and heparinized saline in the maintenance of radial arterial line patency. However, the use of a continuous heparinized flush solution in pressurized arterial lines is beneficial in that it results in greater accuracy of blood pressure monitoring than normal saline infusion.

Adult↗