Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Data Accuracy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed1981

[Computer compatible long-term ECG analysing system for quantitative detection of low grade and complex dysrhythmias--Methods and evaluation of the analysing accuracy (author's transl)].

On the basis of a commercially available analyser2) a long-term ECG analysing system for quantitative detection of the following events was developed: all QRS complexes, ventricular premature beats (VPB), VPB with different coupling intervals (including the R/T phenomenon), paired VPB, salvos of VPB, ventricular tachycardias, ventricular bigeminy, supraventricular premature beats, supraventricular tachycardias, and asystoles. These dysrhythmias are detected simultaneously at 60-fold speed and counted within predeterminable time intervals, the results being printed out and at the same time stored on punch tape, thus allowing off-line computer processing of the data. The accuracy of the analysing system working in a fully automatic mode was evaluated by comparison to the results obtained by two cardiologists. The predictive value of the analyser was 99.9% for all QRS complexes and 97.2% for aberrantly shaped QRS complexes. The corresponding values of the sensitivity were 99.7% and 95.3%. For paired VPB or salvos of VPB and ventricular bigeminy the predictive value was 91.8% and 95.1%, respectively, the sensitivity being 93.4% and 87.9%, respectively. For the detection of asystoles, in spite of a 100% sensitivity a predictive value of only 45.6% was found. Therefore these events may well be detected automatically, but the false positive counts will have to be sorted out by visual inspection on the oscilloscope or ECG write-out.

Arrhythmias, Cardiac↗
PubMed2001

Methodological considerations when conducting direct observation in an outdoor environment: our experience in local parks.

OBJECTIVE: This paper discusses some of the inherent methodological limitations of gathering data via direct observation using local parks as a case study. METHODS: Direct observation was carried out in five parks on seven non-consecutive days in 1998 and on matched days in 1999. Information recorded for each person included the time of park entry and exit, gender, age group, and activity/ies undertaken while in the park. METHODOLOGICAL CONSIDERATIONS: The location of the observation point, observer reliability, recording and accuracy of data, and specific issues related to outdoor observation areas should all be considered when designing a study incorporating direct observation as a data collection method. CONCLUSIONS: Direct observation can provide valuable information. However, pilot testing is essential for minimising potential problems associated with this method and optimising data quality. IMPLICATIONS: The issues discussed in this paper provide a useful guide for other researchers undertaking direct observation in outdoor environments.

Data Collection↗
PubMed2005

Development of a multicenter peripheral arterial interventional database: the PVD-QI2.

BACKGROUND: The number of peripheral vascular intervention (PVI) procedures performed is steadily increasing in the United States. PVD-QI 2 is a prospective, multicenter observational study designed to improve the quality of care for patients undergoing PVI and to better understand the effectiveness and appropriateness of PVI in improving outcomes of peripheral arterial disease. The registry aims to elucidate which comorbid conditions and procedure-related variables are associated with beneficial or adverse outcomes after vascular interventions. METHODS: Five centers are currently prospectively collecting data on consecutive PVIs performed at their institutions and will include patients with both claudication and critical limb ischemia. A common data collection form and a standard set of definitions were developed during several planning meetings. Information on patient demographics, clinical history, comorbid conditions, treatment approaches, and in hospital outcomes are being collected. Patients will be followed up at 30 days, 6 months, and 1 year after each procedure to identify recurrent vascular events, medication use, lifestyle modifications (regular exercise, dietary modification), self-reported walking scores, and mortality. Data validity will be assured through review of data form accuracy by a trained nurse, by automatic database diagnostic routines, and by site visits that include review of angiography suite logs and randomly selected charts. CONCLUSIONS: The development of a quality-controlled PVI registry requires the commitment and collaboration of clinician-investigators and hospital systems devoted to understanding factors that contribute to quality outcomes. Central to achievement of this goal is the creation of a careful diagnostic and data quality assessment system. This registry will provide important clinical insights into patient demographic and clinical characteristics, procedural characteristics, and current practice patterns that foster or impede achievement of long-term quality-based clinical outcomes for patients with peripheral arterial disease.

Databases, Factual↗
PubMed2002

Reproducibility of glucose measurements using the glucose sensor.

OBJECTIVE: Recent studies have confirmed that improved glycemic control decreases the risk of diabetic complications in type 1 and type 2 diabetic patients. The Minimed glucose sensor allows continuous 72-h glucose monitoring and represents a potentially important tool to improve diabetes management. Its use is currently limited to the health care team. Our aim was to evaluate the reproducibility of data provided by the device by comparing data provided by two sensors worn simultaneously by the same subject. RESEARCH DESIGN AND METHODS: A total of 11 subjects (6 type 1 and 3 type 2 diabetic patients and 2 healthy subjects) agreed to wear two sensors and perform at least four daily finger-stick glucose determinations during 72 h. The simultaneous glucose values provided by the sensors were compared. To determine the clinical implications of the glucose data, each day was divided into eight periods, and for each period the glucose range was rated as satisfactory, too high, or too low by a blinded clinician experienced in interpreting glucose sensor data in the clinical setting. The evaluation of glycemic levels based on the recordings of the two sensors were compared for each paired time interval. RESULTS: We discarded 18% of the sensor data for technical reasons. Examined as a group, the remaining 3,370 paired data points in all 11 patients were highly correlated (r = 0.84). However, when individual pairs were evaluated, large differences in the glucose values were apparent, with differences of >10% in 70% of the measurements and >50% in 7% of the measurements. Moreover, clinical evaluation of the glucose range provided simultaneously by two sensors was concordant for only 65% of the evaluation periods. CONCLUSION: In a real-life setting, the accuracy of data provided by the Minimed glucose sensor may be less than expected. To avoid therapeutic errors, sensor findings should be confirmed by independent means before clinical decisions are made.

Blood Glucose↗
PubMed2002

Self-marking of anatomical landmarks for on-orbit experimental motion analysis compared to expert direct-marking.

The on-orbit application of movement analysis methodology, on-board space stations, for studying the gravity role in motor functions, requires a careful adaptation of the currently adopted techniques in order to obtain reliable data. In those operative conditions, differently from common on-ground experimental activities, a non-specialist operator, an astronaut of the space station crew, is expected to self-administer the experimental protocol, particularly self-marking specific anatomical landmarks. The present paper proposes a movement analysis methodology, which fits the specific constraints of space activity and matches the objective of maximising reliability and minimising on-orbit time, and reports normative data about accuracy and precision of the self-marking of an extended set of anatomical landmarks. The same set of landmarks has been considered also for direct-marking performed by experts in motion analysis and their results have been compared to self-marking ones. The paper contents will support the design of future space experimental campaigns and is, in general, applicable to any on-ground scientific investigation, possibly increasing data reliability.

Adult↗
PubMed1989

Improved energy prediction equations for dairy cattle rations.

The objective was to develop equations that would accurately predict energy contents of rations commonly fed to milking cows and that were simple to apply. Six published equations that predicted TDN from ration content of crude fiber or ADF or predicted digestible energy, metabolize energy, or NE(1) from ration ADF content were modified to remove bias caused by dietary fiber contents. The modified equation that predicted metabolizable energy from ADF was tested for accuracy using data from several feeding trials in which DM intakes and dietary ADF contents were known. Dietary metabolizable energy content calculated by the equation was multiplied by DM consumed to obtain metabolizable energy intake. Requirement of dietary metabolizable energy was calculated using factors for maintenance, milk produced, and BW changes from 1988 NRC feeding standard. Concurrence values (energy intake/energy required) from feeding trials were calculated and served as the criterion of equation accuracy. Several trials resulted in concurrence values approximating 1.0, indicating that the equation to predict dietary metabolizable content was accurate. However, values for individual trials ranged from .84 to 1.21. Concurrence values that deviated considerably from 1.0 occurred most frequently in trials in which animals experienced negative or large changes in BW. It appeared that errors may have occurred in calculating energy requirements when BW changes were negative or large. It was concluded that the modification improved the original equation and it probably was accurate. The other modified equations would be expected to be equally accurate.

Animal Feed↗
PubMed1993

Round and round it goes: the epidemiology of childhood lead poisoning, 1950-1990.

In the 40 years from 1950 to 1990, lead epidemiology and public policy based on it made enormous strides. Exposure levels that caused concern in the medical and public health community fell from 80 to 10 micrograms/dL of blood. In the space of 20 years, beginning in 1970, first the surgeon general and then the CDC lowered the official "level of concern" from 50 or 60 to 10 micrograms/dL. The public health community has turned its attention from the prevention of poisoning that results in encephalopathy, mental retardation, and death to the reduction of exposure to avoid subtle neurobehavioral deficits that are detectable only in fairly large epidemiological studies. Numerous advances in technology and analysis have facilitated progress in lead epidemiology. In order to show that intellectual deficits were related to lead exposure rather than to such confounding variables as parental education, parental IQ, income, or parents' age at time of birth, researchers performed extensive regression analyses of fairly large sample populations, controlling for as many as 39 confounding variables. These analyses would have been virtually impossible but for the development of computer software programs that became available beginning in the late 1960s and early 1970s. Handling of large data bases, such as NHANES II, also required access to computer hardware and software not generally available earlier. The existence of the data depended on other technological innovations that made screening of large populations inexpensive and relatively simple. In 1973, erythrocyte protoporphyrin screening transformed testing for lead poisoning. With the advent of atomic absorption spectroscopy and rapid improvement in equipment for blood lead analysis, obtaining blood lead levels became less expensive and easier and produced more accurate results. Increasing attention both to preventing environmental contamination of samples and to controlling laboratory quality also improved the accuracy of data collected. Advances in screening and analytical technology made the mass screening of the 1970s possible--both the programs coordinated by the CDC and NHANES II. NHANES II showed the extent of the problem of lead exposure to be even greater than previously thought. It was estimated that in 1980 almost 2 percent of all children aged six months to five years had blood lead levels over the CDC level of concern of 30 micrograms/dL. More than 13 percent of black children had levels above 30 micrograms/dL. Lead was certainly the most widespread threat to child health in America. In 1985, when the CDC lowered the level of concern to 25 micrograms/dL, the population defined to be at risk tripled.(ABSTRACT TRUNCATED AT 400 WORDS)

Attitude to Health↗
PubMed2003

[Verbal autopsy to measure maternal mortality in rural Senegal].

OBJECTIVES: The aim of this paper is to study the use of verbal autopsy in order to assess maternal mortality indicators in rural settings and to determine the limits and difficulties related to that practice. MATERIAL AND METHODS: This study was carried out in 3 rural sites (Niakhar in the region of Fatick, Bandafassi in Tambacounda region and Mlomp in the region of Ziguinchor). These sites had been under demographic and epidemiological surveillance for several years. Data were collected through two sources: a questionnaire filled out by data collectors during the demographic surveillance and a complementary survey done by an epidemiologist among families completed by information from the registers of health structures. For all female deaths (15-49 years), the detailed sequence of the events leading to the death were stated in a clinical file of verbal autopsy. All the files had been submitted to two independent obstetricians for analysis. The character of maternal death and the cause of the death (direct, indirect ou undetermined) were processed. The discordant cases were submitted to another expert epidemiologist for analysis. The 10th international classification of diseases of WHO was used as a reference to identify maternal deaths and their causes. RESULTS: This demographic surveillance has led to a complete registration of female deaths and the analysis of female deaths has helped to measure maternal indicators during the observed time period. Among the 471 female deaths, 97 maternal deaths were identified in Niakhar, 36 in Bandafassi and 10 in Mlomp. The proportion of maternal deaths was 30.6% in Niakhar, 32.7% in Bandafassi and 22.7% in Mlomp. The ratio of maternal mortality was 575 per 100,000 live births (LB) in Niakhar, 930/100,000 live births in Bandafassi and 436/100,000 LB in Mliomp. The risk of maternal death was 1 women in 21 in Niakhar, 1 in 16 in Bandafassi and 1 in 41 in Mlomp. Maternal mortality rate was 13.3/10,000 reproductive age women in Niakhar, 17/10,000 in Bandafassi and 6.9/10,000 in Mlomp. Sociocultural limits related to interdiction in the society, and language barriers are seen as limits for applying verbal autopsy practices. Also, a lack of precision in data collection because of lack of information delivered by the interviewee or because of lack of experience of the interviewer could be limitations. This study carried out in a rural setting could not show national maternal mortality level. It takes time to complete verbal autopsy leading to excessive cost. CONCLUSION: Verbal autopsy remains an interesting method for measuring maternal mortality. It has advantages in rural areas where many deliveries still occur at home. Further accuracy in data collection is needed for a precise analysis of each case.

Adolescent↗
PubMed2003

Video-assisted thoracoscopic lung biopsy in the diagnosis of diffuse interstitial lung disease. A prospective study.

AIM: Video-assisted thoracoscopic lung biopsy is commonly performed for diagnosis of diffuse interstitial lung disease. This study reports our experience with this technique in terms of diagnostic accuracy, complications and appropriate site for biopsy. METHODS: A prospective non-randomized study. SETTING: Thoracic Surgery Department, Chest Diseases Hospital, Kuwait. PATIENTS AND INTERVENTION: 79 consecutive patients undergoing thoracoscopic lung biopsy for diffuse interstitial lung disease from January 1995 to December 2001. Patients were divided into 2 groups; 34 patients with single biopsy from lingula or right middle lobe (RML) and 45 with 2 biopsies from other sites. MEASURES: comparison of operative and postoperative data, diagnostic accuracy, and complications between the two groups. RESULTS: The mean age of the patients was 38.9 years (range 15-75 years). There was no difference in the groups in operative time, 24 hours postoperative pleural drainage, chest tube drainage days, and hospital stay. Histologic diagnosis was achieved in 76/79 patients (96%). The diagnostic yield of each group was comparable (32/34 from lingula/RML; 44/45 other sites), (p=0.3). Postoperative complications occurred in 4/34 of patients with single biopsy from lingula or RML and 4/45 patients with 2 biopsies from other sites (p=0.6). There was 1 death in this series. CONCLUSIONS: Video-assisted thoracoscopic lung biopsy is an effective procedure. Single lung biopsy from lingula or RML compared to other anatomic sites has an equivalent diagnostic yield.

Adolescent↗
PubMed1992

Keyless data capture: emerging technologies in health information processing.

As middle managers, medical record practitioners will be involved in justification of auto ID technology to upper management. To prepare a good justification, one must have a thorough knowledge of the technology and its advantages and disadvantages. One must also be familiar with the payback period and the installation process. This article has attempted to introduce the reader to some emerging technologies in health care, and answer some of the questions that are key to justifying their acquisition. By most estimates, these technologies are finding their way into health care, however slowly, and hold much promise for improvement in productivity and accuracy in data collection.

Computer Communication Networks↗
PubMed2026

Wearable wrist-watch type cuff oscillometric blood pressure monitors: consensus statement by the European Society of Hypertension Working Group on blood pressure monitoring.

Wearable wristwatch-type cuff oscillometric blood pressure (BP) monitors represent a new category of BP devices and are the first wearable monitors to use established cuff-oscillometric BP measurement technology. This consensus statement by the European Society of Hypertension Working Group on BP Monitoring reviews the published evidence on their design, accuracy, validation, clinical application, and remaining research questions. Of 281 articles identified through a systematic PubMed search, 26 were relevant. Several devices are currently available; however, only two have published validation studies performed according to established standards (Omron HeartGuide and Huawei Watch D/D2). Static validation studies generally showed acceptable accuracy, whereas data on 24-h ambulatory use, in special populations, and clinical applications remain limited. Potential advantages include self-initiated measurement at home, at work, and in other settings and conditions; more convenient and repeatable 24-h ambulatory monitoring; more convenient and accurate assessment of asleep BP; capture of stress-related and other BP-related episodes. However, proper wrist position, user adherence, ambulatory performance, and clinical applications require further investigation. More research is needed to establish the accuracy and clinical utility of these novel devices and their role in improving the diagnosis and management of hypertension.

Humans↗
PubMed2000

Identification of uncommon plant metabolites based on calculation of elemental compositions using gas chromatography and quadrupole mass spectrometry.

Unknown compounds in polar fractions of Arabidopsis thaliana crude leaf extracts were identified on the basis of calculations of elemental compositions obtained from gas chromatography/low-resolution quadrupole mass spectrometric data. Plant metabolites were methoximated and silylated prior to analysis. All known peaks were used as internal references to construct polynomial recalibration curves of from raw mass spectrometric data. Mass accuracies of 0.005 +/- 0.003 amu and isotope ratio errors of 0.5 +/- 0.3% (A + 1/A), respectively, 0.3 +/- 0.2% (A + 2/A), could be achieved. Both masses and isotope ratios were combined when the elemental compositions of unknown peaks were calculated. After calculation, compound identities were elucidated by searching metabolic databases, interpreting spectra, and, finally, by comparison with reference compounds. Sum formulas of more than 70 peaks were determined throughout single GC/MS chromatograms. Exact masses were confirmed by high-resolution mass spectrometric data. More than 15 uncommon plant metabolites were identified, some of which are novel in Arabidopsis, such as tartronate semialdehyde, citramalic acid, allothreonine, or glycolic amide.

Amino Acids↗
PubMed2003

Echocardiographic evaluation of umbilical venous catheter placement.

OBJECTIVE: To compare techniques for guiding and confirming placement of umbilical venous catheters (UVCs) using two-dimensional echocardiography. STUDY DESIGN: Fifty-three newborns admitted to our neonatal intensive care unit who required an UVC or who were transferred within 24 hours of UVC placement at a referring hospital were studied. UVC position was assessed by antero-posterior (AP) chest radiography (CXR), lateral CXR, and oxygenation data. The accuracy of the above techniques was compared to echocardiography with saline contrast injection. RESULTS: Echocardiography revealed that UVCs were located ideally at the right atrial/inferior vena cava junction in only 12 (23%) of 53 patients. Twenty-four (45%) were incorrectly positioned in the left atrium. The sensitivity and specificity of AP CXR in evaluating inappropriate UVC position were 32% and 89%, respectively. Lateral CXR and thoracic level on AP CXR did not predict accurately catheter position. UVC pO(2) data were not useful in excluding left atrial placement. CONCLUSION: Current methods to determine insertion length and confirm location of UVCs are not adequate. Echocardiography should be considered to confirm correct placement of UVCs.

Catheterization, Peripheral↗
PubMed1997

A triple-head SPECT system with parallel-hole collimators of different acceptance angles.

We proposed to use three different parallel-hole collimators for a triple-head SPECT system. One of the collimators had a small collimator acceptance angle to provide ultra-high spatial resolution and the other two had larger collimator acceptance angles to achieve high counts. A new 2D reconstruction algorithm that combined the data acquired from different collimators was derived to take advantages of both high resolution and high sensitivity. The algorithm was evaluated using a computer-simulated matrix of spherical sources. For noise-free data, the accuracy (mainly determined by spatial resolution) obtained from combination of the collimator acceptance angles of 1.35, 4.05 and 6.75 degrees (or 1.35, 5.40 and 9.45 degrees) was slightly inferior to that obtained from three same LEHR collimators (with a 2.70 degrees collimator acceptance angle). This is because the modulation transfer function (MTF) resulting from three different collimators decreases more quickly at low frequencies but becomes comparable at high frequencies as compared with the MTF of the 2.70 degrees collimator. With noisy data, however, the image quality obtained with three different collimators was better than that resulting from any combinations of three same collimators. The improvement was only achieved by using the derived algorithm, while the conventional FBP algorithm did not improve image quality even with the same collimator configuration.

Algorithms↗
PubMed2006

Evaluation of spoken dialogue technology for real-time health data collection.

BACKGROUND: A real-time assessment of patients' experiences is an important methodology for studies in health care, quality of life, behavioral sciences, and new drug and treatment development. Ecological momentary assessment is a methodology that allows for real-time assessment of experience and behavior in a subject's natural environment. Recently, electronic data collection techniques have been introduced, including systems utilizing interactive voice response. OBJECTIVE: The objective of this project was evaluation of spoken dialogue methodology for real-time data collection of information from patients for health, behavioral, and lifestyle studies and monitoring. While the management of the data collection process was Internet-based, this additional eHealth communication channel was based on over-the-phone natural language conversation with a dialogue system utilizing automated speech recognition technology. For this study we implemented a dialogue system for patients' assessment and monitoring of chronic pain. METHODS: Experimental evaluation of usability of the Pain Monitoring Voice Diary was performed with 24 volunteers. The volunteers were asked to contribute 10 sessions with the system over a period of 2 weeks; in practice, the number of sessions per subject ranged from 1 to 20. The subjects were asked to either relate to pain episodes in their past while answering the system's questions, or use as a guidance one of nine provided medical scenarios compiled by a pain specialist, ranging from migraines and back pain to post-surgical pain (knee injury) and cancer- and chemotherapy-related afflictions. RESULTS: From 24 volunteers, we collected a total of 177 dialogue sessions: 171 sessions were completed, while the caller hung up in the other 6 sessions. There were a total of 2437 dialogue turns, where a dialogue turn corresponds to one system prompt and one user utterance. The data capture rate, measuring the percentage of slots filled automatically, was 98%, while the other 2% were flagged for transcription. Among the utterances sent to transcription, where the user had opted for the "none of those" option, 70% corresponded to the "type of pain" slot, 20% to the "symptoms" slot, and 10% to the "body part" slot, indicating that those are the grammars with the highest out-of-vocabulary rate. CONCLUSIONS: The results of this feasibility study indicated that desired accuracy of data can be achieved with a high degree of automation (98% in the study) and that the users were indeed capable of utilizing the flexible interface, the sessions becoming more and more efficient as users' experience increased, both in terms of session duration and avoidance of troublesome dialogue situations.

Adaptation, Psychological↗
PubMed1996

Validity of occupational exposure and smoking data obtained from surviving spouses and colleagues.

The accuracy of exposure data from surrogate sources such as spouses and colleagues was estimated in an historical cohort of 10,059 metal workers. In a 2 year period from 1986 to 1988, 118 subjects who, in 1986, answered a questionnaire on occupational exposures and smoking habits had died. In 1988 spouses and long-term colleagues were interviewed on the same items. Separate contingency tables were developed comparing case and spouse/colleague responses. Percentage of concordance, sensitivity, specificity, the kappa measure of agreement, and a bias factor (exposed to nonexposed ratio between surrogates and cohort members) were calculated. Compared with the index subjects indications, the colleagues' and spouses' reports represented a moderately high level of concordance on occupational exposures, primarily for exposures with a moderate prevalence. There was a considerable under-reporting on both occupational exposures and smoking habits expressed in low values of sensitivity and bias factor values below one. The described misclassification of exposure data by using surrogate information might seriously influence the risk estimation and introduce bias.

Asbestos↗
PubMed2004

Sources of variation and bias in studies of diagnostic accuracy: a systematic review.

BACKGROUND: Studies of diagnostic accuracy are subject to different sources of bias and variation than studies that evaluate the effectiveness of an intervention. Little is known about the effects of these sources of bias and variation. PURPOSE: To summarize the evidence on factors that can lead to bias or variation in the results of diagnostic accuracy studies. DATA SOURCES: MEDLINE, EMBASE, and BIOSIS, and the methodologic databases of the Centre for Reviews and Dissemination and the Cochrane Collaboration. Methodologic experts in diagnostic tests were contacted. STUDY SELECTION: Studies that investigated the effects of bias and variation on measures of test performance were eligible for inclusion, which was assessed by one reviewer and checked by a second reviewer. Discrepancies were resolved through discussion. DATA EXTRACTION: Data extraction was conducted by one reviewer and checked by a second reviewer. DATA SYNTHESIS: The best-documented effects of bias and variation were found for demographic features, disease prevalence and severity, partial verification bias, clinical review bias, and observer and instrument variation. For other sources, such as distorted selection of participants, absent or inappropriate reference standard, differential verification bias, and review bias, the amount of evidence was limited. Evidence was lacking for other features, including incorporation bias, treatment paradox, arbitrary choice of threshold value, and dropouts. CONCLUSIONS: Many issues in the design and conduct of diagnostic accuracy studies can lead to bias or variation; however, the empirical evidence about the size and effect of these issues is limited.

Bias↗
PubMed2005

Development and validation of a gradient HPLC method for the determination of clindamycin and related compounds in a novel tablet formulation.

A gradient reversed-phase HPLC method was developed and validated for potency, content uniformity, and impurity determinations for a novel tablet formulation containing clindamycin. The assay utilized UV detection at 214 nm and a Waters Xterra RP18 column (4.6 mm x 100 mm, 3.5 microm). The mobile phases were comprised of pH 10.5, 10 mM carbonate buffer and acetonitrile. Validation experiments were performed to demonstrate specificity, linearity, accuracy (i.e., average recovery from the formulation), precision (i.e., repeatability), limit of quantitation (LOQ), and robustness (i.e., sample solution stability and buffer pH effects on specificity). The assay was shown to be specific for clindamycin, several impurities, and triethyl citrate, a retained excipient that was present in the dosage form. The assay was proved linear (concentration versus peak area) for clindamycin and several select impurities over the ranges of 70-130% and 0.1-5%, respectively. UV relative response factors were determined for the impurities from the linearity data. The accuracy of clindamycin at the targeted assay concentration was 99.2% (n = 3; precision = 0.12%, R.S.D.); accuracy for lincomycin, a structurally related impurity, was 97.4% (n = 3; precision = 3.5%, R.S.D.) at 0.1% of the targeted assay concentration. By demonstrating an acceptable degree of precision for lincomycin at this level, the LOQ was shown to be no higher than 0.1%. The chromatography was virtually unaffected over a mobile phase buffer pH range spanning 0.4 pH units. Sample solutions were stable for 72 h under ambient conditions.

Chemistry, Pharmaceutical↗