SEARCH · PubMed Health

Results for “Reproducibility”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 1,081 records · Page 60Linked to original sources

PubMed2002

An investigation of the repeatability and reproducibility of ISO 11948-1 (the Rothwell method) for measuring the absorption capacity of incontinence pads.

The repeatability and reproducibility (precision within and between laboratories, respectively) of an international standard method (ISO 11948-1, the Rothwell method) for measuring the absorption capacity of incontinence pads was investigated. The 74 shaped disposable bodyworn insert pads for heavy incontinence on the UK market in spring 1997 were tested in three laboratories experienced in using the method, one in each of England, Spain and Sweden. Coefficients of variation (standard deviation as a proportion of the mean) for five repeats rarely exceeded 5% within any laboratory. However, there were systematic differences between laboratories: results from the Swedish and Spanish laboratories typically exceeded those from the English laboratory by 13% and 8%, respectively. The good repeatability suggests that the method is capable of adequate precision but the poor reproducibility implies that the instructions in the standard for building and/or using the test apparatus are inadequate, leaving too much room for interpretation. Having studied the data presented here and viewed videos of the apparatus in use in five laboratories (including the three contributing to this note) the ISO working group which wrote the original standard has identified several likely sources of imprecision and is now working to revise the standard to improve its reproducibility.

England↗

PubMed2003

Reproducibility of the measurement of the muscle ergoreflex activity in chronic heart failure.

BACKGROUND: A causative role for symptom generation in heart failure has been attributed to overactive muscle afferents, metaboreflex and mechanoreflex. We examined the reproducibility of the methods commonly used to assess these reflexes. MATERIAL AND METHODS: Twelve stable heart failure patients (62.8+/-2.4 years) and 18 normals were studied. The metaboreflex was evaluated on both leg and arm exercises, by performing two runs of 5-min submaximal handgrip and leg exercises. On one run the subjects recovered normally (control recovery), while on the other a post-exercise regional circulatory occlusion (PE-RCO) was induced in the exercising limb, to isolate the stimulation of the metaboreceptor after exercise. The metaboreflex was quantified as the difference in ventilation between the PE-RCO and the control recovery periods with respect to rest. The existence of a mechanoreflex was sought by comparing the ventilatory increment per unit of active work (dV(E)/dVO(2) ratio) between leg passive movement and active low level exercise. The coefficients of variation (CV) were computed to express the reproducibility of these reflexes in heart failure. RESULTS: The metaboreflex was overactive in patients vs. normals during both arm (7.2+/-2.8 l/min vs. 0.06+/-0.3 l/min) and leg (5.6+/-1.2 l/min vs. 0.5+/-0.2 l/min) tests. The mechanoreflex was not different between patients and normals: dV(E)/dVO(2) during passive movement 48.9+/-18.3 and 22.4+/-26.5; active exercise 42.3+/-18.4 and 31.9+/-18.7 (P=NS). In patients, the CV for the metaboreflex was 23.4% in the arm and 35.3% in the leg, while for the mechanoreflex test CV was 38.1% during passive movement and 21.1% during active exercise. CONCLUSION: The described method of measuring the muscle reflex activity shows an adequate reproducibility in heart failure patients.

Chemoreceptor Cells↗

PubMed1998

Reproducibility of knee laxity assessment results using the dynamic cruciate tester.

The purpose of the study was to examine reproducibility of knee laxity measurements obtained using the Dynamic Cruciate Tester (DCT) from day-to-day, set-to-set, and trial-to-trial. In Part I, peak anterior tibial translation (ATT) was assessed for 1 anterior cruciate ligament (ACL) deficient and 16 control subjects during two sets of three active trials (maximal isometric quadriceps contractions) and three passive trials (240 N load) conducted over four consecutive days. In Part II, peak ATT was recorded for 12 chronic ACL deficient subjects during one set of five active and five passive trials within one day. Results were analysed using mixed repeated measures ANOVA designs with intraclass reliability coefficients (ICC) calculated from the ANOVA results. There were no significant differences in the mean peak ATT results among the four tests days or between the two test sets conducted within a day, with ICC ranging from R1 = 0.939 to 0.980. It was concluded peak ATT measurements obtained using the DCT were reproducible from day-to-day and set-to-set. A significant main effect of trial was found on both active (F(2,32) = 13.93; p < 0.001) and passive (F(2,32) = 57.21; p < 0.001) peak ATT results. It was therefore recommended a full pretrial should be conducted before knee laxity assessment using the DCT to ensure reproducible results.

Adult↗

PubMed2003

Intraindividual reproducibility of nasal allergic responses to diesel exhaust particles indicates a susceptible phenotype.

Previous research indicates that diesel exhaust particles (DEP) can augment allergen- driven allergic responses. In vivo nasal challenge offers a practical method to characterize variation in response to pulmonary toxicants and immunogens. We investigated the reproducibility of responses to determine whether susceptibility to DEP's adjuvant effects is intrinsic or extrinsic. Eighteen nonsmoking rhinitic volunteers with positive skin tests to ragweed were randomly assigned to allergen/placebo or allergen + DEP nasal challenge; after 30 days, the other "arm" was completed. We replicated the procedure 30 days later. Nasal washes were performed after challenge, and allergen-specific IgE and cytokines were measured by ELISA. Repeated challenge with allergen+DEP, but not allergen/placebo, produced reproducible responses for IgE, IL-4, and INF-gamma. DEPs ability to enhance allergic responses was highly reproducible within individuals and was independent from response to allergen, suggesting that susceptibility to DEPs adjuvant effects is an intrinsic trait that can be quantified using combined allergen + DEP challenges.

Adolescent↗

PubMed2005

Assessing reproducibility of a protein dynamics study using in vivo labeling and liquid chromatography tandem mass spectrometry.

Measuring dynamics of proteins abundance in cells in response to stimuli such as growth factors or drugs requires analysis of more than one time point. Proteomic approaches have traditionally been used to measure only one state at a time because quantitation is difficult, especially when mass spectrometry is used as a readout. Isotopically labeled reagents have recently been introduced that allow comparison of two or three different states by mass spectrometry. Here, we evaluate the reproducibility of an experiment that measures three states simultaneously through stable isotope labeling of cells with amino acids in cell culture (SILAC) using light, medium, and heavy versions of amino acids. The major goal of this study was to assess the reproducibility of such experiments in combination with liquid chromatography tandem mass spectrometry (LC-MS/MS). Our results show that it is possible to obtain reproducible quantitative data to study protein dynamics based on our analysis of more than 220 peptide sets derived from 20 proteins from 3 different LC-MS/MS runs.

Arginine↗

PubMed2026

2-Mercaptoethanol/DMSO Workflow Enables Highly Reproducible Quantitative Proteomics.

Proteomics provides a systematic and high-throughput approach to comprehensively characterize protein networks, enabling insights into cellular functions and disease mechanisms. Carbamidomethylation using iodoacetamide (IAA), a common method for cysteine alkylation, is known to cause nonspecific modifications that increase spectral complexity in mass spectrometry and reduce quantitative accuracy. Here, we established a reproducibility-focused 2-mercaptoethanol (2-ME)/dimethyl sulfoxide (DMSO) workflow and systematically evaluated its quantitative performance at the proteome-wide level. Mouse liver proteomes were processed using either 2-ME/DMSO or conventional IAA treatment, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The optimized 2-ME treatment increased the number of cysteine-modified peptides by 1.6- to 1.9-fold. Although total protein identifications were comparable, 77% of proteins exhibited improved sequence coverage with the optimized 2-ME treatment. Quantitative reproducibility was also enhanced, with the peptide quantified CV ≤ 20% increasing from 61.4% with IAA treatment to 86.1% with 2-ME treatment, and protein quantified CV ≤ 20% increasing from 80.6% with IAA treatment to 93.5% with 2-ME treatment. Application of this new workflow to ovarian clear cell carcinoma reliably detected cisplatin-induced alterations. The 2-ME/DMSO workflow offers a simple and highly reproducible proteomics strategy for accurate quantitative proteomics.

Animals↗

PubMed2006

Characterizing the reproducibility of a protein profiling method for the analysis of mouse bronchoalveolar lavage fluid.

The detection of biomarkers in biological fluids has been advanced by the introduction of mass spectrometry screening methods such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS), which enables the detection of the presence and the molecular mass of proteins in unfractionated mixtures. The generation of reproducible mass spectra over the course of an experiment is vital in obtaining data in which differences in protein profiles between diseased and healthy states can be assessed correctly. We have developed a protocol to automate the collection of protein profiling data from a large number of samples using MALDI-TOFMS, and we used these samples to characterize the technical reproducibility of the method. This protocol has been used for the analysis of proteins found in bronchoalveolar lavage fluid samples from mice with the ultimate goal of enabling the discovery of differential expression patterns predictive of the development of chronic obstructive pulmonary disease. Samples were purified using magnetic bead-based technology and analyzed on an AnchorChip target plate. Our results demonstrate that the number of peaks detected reproducibly decreases significantly as sample size increases, which motivates the need for technical replicates to be explicitly included in the analysis of MALDI-TOF-based protein profiling studies.

Acrolein↗

PubMed1999

Reproducibility of volumetric macular measurements in diabetic patients with the Heidelberg Retina Tomograph.

AIMS: To quantify diabetic macular edema by confocal scanning laser ophthalmoscopy and assess its usefulness by determining the reproducibility of topographic measurements at the macula. METHODS: The volumes above reference plane bound by a 2 mm diameter circle centred on the fovea were measured by two observers. The reference plane was adjusted to the lowest point of the height variation of the contour line. The reproducibility of this technique was assessed in 20 eyes of 20 diabetic patients of which 8 eyes had macular edema. Three HRT scans of each eye were obtained. The measurements of volume above reference plane of each scan were repeated three times. RESULTS: For all diabetic eyes, the intra scan coefficients of variability measured 14.71% to 21.21%, the inter scan coefficient of variability was 30.46%. The average standard deviations were 0.053 mm3 for one examination per scan, 0.047 mm3 for two examinations per scan and 0.044 mm3 for three examinations per scan. Linear regression demonstrated an increase in standard deviation with greater volumetric measurements (p < 0.001). We found good correlation (r = 0.959, p < 0.001) and strong agreement between the two observer's findings for all 20 eyes. For the 8 eyes with macular edema, the coefficients of variability were similar to those calculated for all 20 eyes. The average SD for one examination per scan were 0.078 mm3, 0.069 mm3 for two examinations per scan and 0.062 mm3 for three examinations per scan. We found good correlation (r = 0.945, p < 0.001) and strong agreement between the two observer's findings in eyes with edema. CONCLUSION: The reproducibility of this technique has been demonstrated in diabetic eyes. This may have useful clinical applications for the quantification of diabetic macular edema and monitoring of laser therapy.

Adult↗

PubMed1997

Reproducibility of stress echocardiography using intravenous injection of ultrasound contrast agent (BY 963).

UNLABELLED: Despite the widespread use of stress echocardiography, its reproducibility is still limited by high interobserver variability. Therefore, the purpose of the present study was to improve the reproducibility of a stress (exercise) echocardiography using a new transpulmonary ultrasound agent (BY 963). Stress echocardiography was performed in 12 healthy volunteers with suboptimal endocardial border delineation during exercise echocardiography. A special 45 degrees lateral tilted bike stress echocardiography table was used for exercise testing. Echocardiographic images were recorded on-line at rest and during exercise on a video tape and additionally digitized on-line on a stress echo computer. End-diastolic (EDVml), end-systolic (ESVml) volume and ejection fraction (EF%) were estimated in the 4-chamber view. The measurements were performed before and after injection of 2.5 ml and 5 ml BY963 at rest and in maximal exercise. A new contrast agent (BY 963) leads to a sufficient contrast effect for the left ventricular cavity after intravenous administration and permits a good delineation of left the endocardial border. The interobserver variability was determined using blinded investigation by two observers. The correlation of EDV and ESV determination at rest was r = 0.68/0.33, after 2.5 ml BY 963 r = 0.97/0.93 and after 5 ml BY 963 r = 0.90/0.93. The correlation for EDV and ESV during exercise was r = 0.52/0.33, after 2.5 ml BY 963 r = 0.88/0.80 and after 5 ml BY 963 r = 0.95/0.92. At rest mean EF without contrast was 61 +/- 6%/67 +/- 7% (r = 0. 130), after 2.5 ml BY 963 i.v. 69 +/- 8%/72 +/- 7% (r = 0.82) and after 5 ml BY 963 i.v. 73 +/- 8%/73 +/- 8% (r = 0.98%) respectively. In exercise, mean EF without contrast was 68 +/- 8%/70 +/- 6 (r = 0.013), after 2.5 ml BY 963 83 +/- 6%/81 +/- 5 and after 5 ml 83 +/- 4%/82 +/- 3 (r = 0.86). SUMMARY: The estimation of the end-systolic volume in exercise will be improved significantly and the estimated EF values will be higher compared to EF values obtained without contrast application. Transpulmonary contrast echocardiography for analysis of left ventricular volumes and ejection fraction can be routinely used in stress echocardiography. Intravenous administration of BY 963 improves the reproducibility of quantitative analysis of left ventricular function in healthy volunteers. Further studies in patients with cardiac diseases are required to corroborate this observation.

Adult↗

PubMed2002

Optimising the reproducibility of a performance-based assessment test in midwifery education.

Despite problems concerning generalisability of test results - largely due to limited sampling of the task domain - and questions about test efficiency, the popularity of OSCEs in medical education has motivated the use of similar assessment methods in other health care domains. Purpose of this study was to investigate reproducibility of scores on an OSCE-based test in the relatively narrow domain of midwifery, as compared to the broad medical domain. The influence of global rating scales and adoption of a mastery-oriented test perspective on reproducibility of test scores was investigated in order to explore possibilities to increase test efficiency.A 3-hr, 6-station performance based test was administered to third and fourth year students at Kerkrade Midwifery School (the Netherlands). Students' performance was recorded using a station specific checklist and a global rating scale. For the 3-hr OSCE the generalisability coefficient based on checklist scores is 0.48. Based on global ratings alone, the generalisability coefficient is 0.61. Adjusted dependability indices are 0.85 based on checklist scores and 0.95 for global ratings respectively. Results suggest that even for small domains the problem of case-specificity remains a major impediment to high stakes performance testing. Findings furthermore suggest that use of global rating scales and professional expert judgements in professional competence evaluation is to be preferred to task specific checklists for reasons of reproducibility and efficiency in test development and administration. Adoption of a mastery oriented test perspective may reduce testing time requirements even further.

Certification↗

PubMed2003

Reproducibility of the lactate stress test.

Although the lactate stress test has been shown to be a powerful tool to screen for respiratory chain disorders, little is known about the reproducibility of this test. The aim of the present study was thus to look for the reliability of the lactate stress test in disease controls and patients with primary respiratory chain disorders. In 23 patients with respiratory chain disorder, 16 women and 7 men, aged 36-81 years, and 18 disease controls, 5 women and 18 men, aged 37-70 years, the lactate stress test was carried out when respiratory chain disorder was suspected for the first time and at the first follow-up. The sensitivity of the first lactate stress test was 81% and the specificity 72%. The sensitivity of the second lactate stress test was 74% and the specificity 61%. The reproducibility of the lactate stress test was 65% in patients with respiratory chain disorders and 78% in disease controls. In conclusion, this study shows that the sensitivity, specificity, and reproducibility of the lactate stress test is high enough to warrant its application as a reliable, supplementary method to search for respiratory chain disorders.

Adult↗

PubMed2004

A way to improve the reproducibility of measurements of myocardial velocity gradients.

BACKGROUND: A peak negative myocardial velocity gradient (MVG) across the left ventricular wall is an important indicator of diastolic performance. The reproducibility of MVG measurements by color M-Mode tissue Doppler imaging (TDI) is still unsatisfactory, restraining its use in clinical practice. Aim of the study was to improve the reproducibility of measurements of MVG. METHODS: The peak diastolic MVG of left ventricular posterior wall was determined in 50 consecutive patients by two investigators in two ways: (1) using directly standard anatomic color M-Mode TDI and (2) by the same technique, but guided by a preliminary MVG estimation with pulsed TDI using four measurement sets within the ventricular wall. RESULTS: The interobserver agreement limits of the combined method [-0.78 s(-1) (95% CI: -0.95 to -0.6 s(-1)) to 0.57 s(-1) (95% CI: 0.4-0.75 s(-1))] were clearly superior to those shown by color M-Mode TDI without B-Mode pre-assessment [-1.35 s(-1) (95% CI: -1.72 to -0.98 s(-1)) to 1.5 s(-1) (95% CI: 1.13-1.87 s(-1))]. CONCLUSIONS: An initial estimation by pulsed TDI is useful to achieve a clinically acceptable reproducibility of MVG measurements.

Diastole↗

PubMed2004

Visceral sensitivity in irritable bowel syndrome and healthy volunteers: reproducibility of the rectal barostat.

The reproducibility of rectal visceral sensitivity using the barostat double-random staircase method was evaluated. We tested 15 healthy women and 18 women with irritable bowel syndrome twice. Pressure, volume, and tension were measured at first sensation of gas, stool, and discomfort. There was no significant difference between test and retest. Three different indexes were used as measures of reproducibility. The intraclass correlation coefficients, considered to demonstrate acceptable reproducibility when higher than 0.80, ranged from 0.76 to 0.93 in the healthy volunteers and from 0.53 to 0.88 in the patients. The pooled coefficients of variation ranged from 10 to 24% in the healthy volunteers and from 11 to 49% in the patients. The repeatability coefficients are also given. The results indicate that barostat visceral sensitivity measurements in the rectum may be applicable when comparing groups of subjects.

Adult↗

PubMed2004

Assessing reproducibility for interval data in health-related quality of life questionnaires: which coefficient should be used?

In contrast to other reliability estimates, test-retest reliability (or reproducibility) captures not only the measurement error of an assessment instrument, but also the stability of the construct measured. Consequently, one would expect any departure from identity (Y = X) of measurement pairs (X first, and Y second measurement) to be treated as 'error' by the respective reproducibility statistic, even if 'true' changes happened, e.g. worsening of a disease due to its natural course. The Pearson correlation, still often advocated for continuous measures in test-retest reliability studies, however captures the degree of linearity (Y = bX + a): perfect relationship can be computed, even if the measurement pairs differ not only by a additive constant 'a', but also because of a multiplication of the X-values with the slope 'b'. Therefore, intraclass correlation coefficients (ICCs) have been proposed as alternative statistics for reproducibility. However, only ICCs with absolute agreement definition of concordance capture the degree of identity. ICCs with a consistency definition of concordance measure the degree of additivity (Y = X + a). ICCs are calculated from repeated measures analyses of variance (ANOVAs), and a common population variance must be is assumed for the different measurements. Given this assumption, an ICC computed from a one-way ANOVA seems to be the best choice for this purpose. Otherwise, Lin's concordance correlation coefficient is recommended as identity measure.

Analysis of Variance↗

PubMed2002

The atopy patch test -- reproducibility and comparison of different evaluation methods.

BACKGROUND: There is still a lack of standardization of the atopy patch test (APT) in test procedures and evaluation methods. Our aim was to examine the reproducibility of APT results and to compare visual evaluation to chromametry and laser Doppler imaging. METHODS: Fifty-two volunteers with atopic eczema/dermatitis syndrome (AEDS) were included. The APT was performed on tape-stripped and unstripped test fields on their backs using cat dander, house dust mite and grass pollen allergens from two different suppliers. Responders were re-tested 4-12 weeks later with the same allergens on their forearms. RESULTS: Using Allergopharma allergens, 14 (26.9%) volunteers showed one or more positive reactions. The reproducibility rate was 56.3%. The Erlangen atopy score in APT-positive and negative volunteers was 19 +/- 6 vs 15 +/- 6. The test agreement in volunteers tested with both allergens, from Allergopharma and Stallergènes, was poor. Correlation of the results between the three evaluation methods was significant (P < or = 0.001). CONCLUSIONS: The low reproducibility rate of APT results and the poor inter-test-agreement using allergens from different suppliers show that much work remains to make the APT a reliable tool in identifying relevant aeroallergens that lead to flare ups of AEDS. Compared to chromametry and laser Doppler imaging, visual scoring was superior in differentiation between irritative and allergic reactions.

Adolescent↗

PubMed1997

Reproducibility of automated periodontal probing around teeth and osseointegrated oral implants.

Three different probing devices (Audio-Probe, Florida-Probe, Peri-Probe) were tested in order to determine the clinical probing depth (CPD) around clinically stable oral implants and their homologous teeth and to evaluate their reproducibility. In all 37 patients, in the age range of 24-80 years, who had undergone periodontal therapy and placement of 1 or more oral implants (ITI), were selected for the study. The CPD was determined on 75 oral implants in total and at 4 sites of both the implants and the control teeth at 3 visits, each 1 week apart. At the 1st visit, the Florida-Probe and the Audio-Probe were used. At the 2nd visit, the Florida-Probe and the Peri-Probe and, at the 3rd visit, again, the Florida-Probe and the Audio-Probe were used. At each visit bleeding on probing (BOP) was registered. A statistically significant (P < 0.05) difference between the mean scores of implant and tooth sites was found showing slightly higher values for implant sites. A tendency for the deeper pockets to bleed more frequently than the shallow pockets was observed. The comparisons of differences of the readings of the Audio-Probe on 2 different occasions were smaller than for the Florida-Probe. However, comparisons between 2 different probes showed significantly greater measurement errors than when comparing the probes alone. There was a tendency for the Peri-Probe to yield the highest and the Audio-Probe the lowest values in inflamed sites. It was concluded that all 3 probing devices appeared to have adequate reproducibility both around teeth and oral implants. For clinical use in daily practice, the Audio-Probe was found to be the most simple device with the highest reproducibility.

Adult↗

PubMed2001

Intra-examiner reproducibility of 4 dental plaque indices.

BACKGROUND, AIMS: The aim of the present study was to assess the intra-examiner reproducibility for 2 established ordinal plaque indices and 2 newly proposed interval plaque indices. METHOD: 15 subjects received a professional tooth cleaning and interrupted all oral hygiene measures for 48 to 62 hours. Plaque accumulation was scored 2x for all canines, premolars and 1st and 2nd molars in the 1st and 3rd quadrants with the visual plaque index (VPI), the modified navy plaque index (mNPI), the axial plaque extension index (APEI) and the proximal plaque extension index (PPEI). 147 teeth (57 molars, 60 premolars, 30 canines) were scored. RESULTS: No statistically significant differences were found for duplicate measurements with all indices, except for buccal and lingual VPI (p < 0.05. Wilcoxon test) and for buccal APEI (p < 0.01, t-test). High correlations existed between all duplicate measurements with r-values ranging from 0.76 to 0.94. For the VPI, 78% of buccal (kappa = 0.70) and 89% of lingual (kappa = 0.75) scores were identical, whereas this was the case for 88% of buccal (kappa = 0.81) and for 73% of lingual (kappa = 0.62) mNPI scores. For APEI and PPEI scores a linear regression was found with slopes ranging between 0.76 and 1.00. For these indices, the mean measurement error ranged between 0.4 and 9.1%. Results were comparable for VPI, mNPI and PPEI, whereas APEI appeared slightly less reproducible. CONCLUSION: In conclusion, a high intra-examiner reproducibility was found for all plaque indices tested, both the ordinal and the interval indices.

Bicuspid↗

PubMed2002

Testing high SPF sunscreens: a demonstration of the accuracy and reproducibility of the results of testing high SPF formulations by two methods and at different testing sites.

BACKGROUND/PURPOSE: The goals of this study were (i) to demonstrate that existing and widely used sun protection factor (SPF) test methodologies can produce accurate and reproducible results for high SPF formulations and (ii) to provide data on the number of test-subjects needed, the variability of the data, and the appropriate exposure increments needed for testing high SPF formulations. METHODS: Three high SPF formulations were tested, according to the Food and Drug Administration's (FDA) 1993 tentative final monograph (TFM) 'very water resistant' test method and/or the 1978 proposed monograph 'waterproof' test method, within one laboratory. A fourth high SPF formulation was tested at four independent SPF testing laboratories, using the 1978 waterproof SPF test method. All laboratories utilized xenon arc solar simulators. RESULTS: The data illustrate that the testing conducted within one laboratory, following either the 1978 proposed or the 1993 TFM SPF test method, was able to reproducibly determine the SPFs of the formulations tested, using either the statistical analysis method in the proposed monograph or the statistical method described in the TFM. When one formulation was tested at four different laboratories, the anticipated variation in the data owing to the equipment and other operational differences was minimized through the use of the statistical method described in the 1993 monograph. CONCLUSIONS: The data illustrate that either the 1978 proposed monograph SPF test method or the 1993 TFM SPF test method can provide accurate and reproducible results for high SPF formulations. Further, these results can be achieved with panels of 20-25 subjects with an acceptable level of variability. Utilization of the statistical controls from the 1993 sunscreen monograph can help to minimize lab-to-lab variability for well-formulated products.

Drug Evaluation↗