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PubMed2005

Sensitivity, specificity, and predictive value of serum soluble transferrin receptor at different stages of iron deficiency.

This study investigated the efficiency of serum soluble transferrin receptor (sTfR) for assessing body iron status at different stages of iron deficiency. Among 72 patients with advanced iron-deficiency anemia (IDA), the sensitivity and specificity of sTfR (at a diagnostic cutoff of 3.24 mg/L) were 70.8% and 90.6%, respectively, with a positive predictive value of 85.0%. Sensitivities of sTfR in patients at the earliest stage of iron deficiency (n=41) and the intermediate stage of iron-deficient erythropoiesis (n=15) were 21.9% and 26.7%, respectively, at the same cutoff value of sTfR. Serum ferritin concentrations averaged 6.7+/-1.9 microg/L in IDA patients with sTfR <3.24 mg/L, which were significantly above the values in IDA patients with sTfR >or=3.24 mg/L (4.8+/-1.2 microg/L, p<0.05). In healthy controls, blood reticulocyte counts were significantly higher in subjects with sTfR >or=3.24 mg/L than in those with sTfR <3.24 mg/L (0.045+/- 0.013 (10(12)/L) vs 0.034+/- 0.011 (10(12)/L), p<0.05]. In conclusion, sTfR level is not a sensitive indicator for the early or intermediate stages of iron deficiency, although sTfR assay can be a useful aid in the diagnosis of advanced IDA. Serum sTfR concentration has significant relationships with blood reticulocyte counts in healthy subjects and with serum ferritin levels in IDA patients.

Adolescent↗

PubMed1988

[Thermography of the breast. Sensitivity, specificity and reproducibility].

Thermography is a questionable method of diagnosis of breast diseases. In our study, we demonstrate that the low sensitivity and specificity is not related to the experience of the reader. One hundred thermograms were given to five different readers: three of them were thermographists, one was a gynecologist and the last one radiotherapist. Sixteen patients had a breast carcinoma, 18 had benign lesions. Seventy-two patients had no lesion at the time of diagnosis and 4 years after. The false negative and the false positive rates were not different according to the readers. The reproducibility, judged with the Kappa test, was poor. This study, in agreement with most of the previous studies, demonstrates that thermography must not be recommended neither for diagnosis nor for screening of breast diseases.

Breast Neoplasms↗

PubMed2006

Hemispheric language dominance in magnetoencephalography: sensitivity, specificity, and data reduction techniques.

Understanding the areas involved in language functions not only enables investigators to understand neuroanatomical structures, but may be a promising technique in the presurgical evaluation of epilepsy. The predictive power of various data reduction techniques was tested on language data obtained by magnetoencephalography (MEG) of 16 patients and 12 control subjects. Words were presented aurally in two phases: the study phase and the recognition phase. Subjects were asked to remember words from the study phase and indicate if they remembered those words during the recognition phase. Single equivalent-current dipoles were calculated to determine laterality indices and the neuroanatomical correlates of language function. For all patients, results indicated a concordance, sensitivity, and specificity of 0.75. After consideration of IQ scores and exclusion from the analysis of those patients with scores below the average range, the results indicated a concordance of 0.90, sensitivity of 0.86, and specificity of 1.00. These findings are consistent with previous MEG investigations of language function in comparison with the Wada technique and support the use of MEG language mapping in most patients with an IQ within or above the average range.

Adult↗

PubMed2002

Evaluation of human papillomavirus testing in primary screening for cervical abnormalities: comparison of sensitivity, specificity, and frequency of referral.

CONTEXT: Human papillomavirus (HPV) DNA testing of women having Papanicolaou (Pap) smears showing atypical squamous cells of undetermined significance (ASCUS) has clinical usefulness. Whether HPV DNA testing alone is useful in primary screening remains to be determined. OBJECTIVE: To determine the accuracy of HPV DNA testing for detecting cervical intraepithelial neoplasia (CIN) grade 3 or cancer (the criterion standard). DESIGN, SETTING, AND PARTICIPANTS: Between December 1997 and October 2000, 4075 women who attended Planned Parenthood clinics in Washington State were screened simultaneously using thin-layer Pap and HPV DNA testing by a polymerase chain reaction (PCR)-based method and by a liquid-based RNA-DNA hybridization capture with signal amplification assay (signal amplification). Women who were positive for high-risk HPV types, or had Pap results of ASCUS or higher, were considered to have positive screening test results and were referred for colposcopy and biopsy. Additionally, a random sample of women with negative screening test results was referred for colposcopy. Based on individual and combined thin-layer Pap, HPV PCR, and HPV signal amplification test results from the screening and the colposcopy visits, 7 colposcopy triage strategies were defined and evaluated. MAIN OUTCOME MEASURE: Sensitivity and specificity for detecting cervical lesions graded CIN 3 or higher for each of the 7 triage strategies. RESULTS: The estimated prevalence of CIN 3 or higher was 3.2%. The sensitivity (95% confidence interval) of thin-layer Pap (with a result of > or = ASCUS) for identifying women with CIN 3 or higher was only 61.3% (48.5%-70.9%) compared with 88.2% (78.9%-93.8%) for HPV testing by PCR and 90.8% (83.1%-95.8%) by signal amplification. Differences in specificities were also observed: 82.4% (81.8%-83.1%) for thin-layer Pap (with a result of > or = ASCUS), 78.8% (77.9%-79.7%) for PCR, and 72.6% (69.4%-75.0%) for signal amplification. Compared with referral for colposcopy of all women with ASCUS or higher, signal amplification testing of women with ASCUS and referral of those with a positive result was about as sensitive (61.3% vs 60.3%, respectively) and significantly more specific (82.4% vs 88.9%, respectively). The strategy requiring repeat positive PCR tests on 2 visits had a sensitivity of 84.2% (75.3%-91.0%) and a specificity of 86.2% (85.1%-87.3%). All tests were more specific and less sensitive in older (> or = 30 years) vs younger women. CONCLUSIONS: Testing for HPV has higher sensitivity but lower specificity than thin-layer Pap screening. In some settings, particularly where screening intervals are long or haphazard, screening for HPV DNA may be a reasonable alternative to cytology-based screening of reproductive-age women.

Adult↗

PubMed1996

Comparison of the sensitivity & specificity of a polyclonal versus monoclonal capture antibody based Bead ELISA for direct detection of cholera toxin from stool specimens.

This study was conducted to examine whether substitution of polyclonal anti-CT IgG (PAb) coated beads with monoclonal anti-CT IgG, (MAb) coated beads would enhance the sensitivity and specificity of the Bead ELISA for direct detection of CT in stool samples of cholera patients. Sensitivity of MAb Bead ELISA was found to be more efficient (92.7%) than the PAb Bead ELISA (88.2%) in comparison to the 'gold standard' method of conventional culture method (CM). However, the MAb based Bead ELISA had lower specificity (45%) than that of PAb Bead ELISA (51.8%). Further, the positive predictive value was also lower in MAb Bead ELISA (69.9%) as compared to PAb Bead ELISA (82.1%). Generally, all the statistical evaluation demonstrated better agreement between PAb (77.9%) and MAb (72.6%) Bead ELISAs in direct detection of free CT and culture method in confirming the causative organism i.e., Vibrio cholerae in stool specimens. When the two assay systems, viz., PAb and MAb Bead ELISAs were compared, the superiority of the PAb Bead ELISA over MAb Bead ELISA was clearly evident as it had 82.4 per cent of agreement value.

Antibodies, Monoclonal↗

PubMed1991

Use of the receiver operating characteristic curve to evaluate sensitivity, specificity, and accuracy of methods for detection of peaks in hormone time series.

We utilize the "Receiver Operating Characteristic" to describe the relationship between sensitivity and specificity as the threshold for peak detection is varied systematically, to provide objective comparison of the performance of methods for detection of episodic hormonal secretion. A computer program was used to generate synthetic data with peaks with variable durations, with constant or variable height, shape and/or interpulse interval. This approach was used to compare the CLUSTER and DETECT programs. For both programs, the observed false positive rates estimated using signal-free data were in good agreement with the nominal rates, but in the presence of signal the observed false positive rates were systematically lower. Sensitivity increases with increasing signal/noise ratio, as expected. Program DETECT, using its standard options, provided excellent sensitivity (90-100%) with very low false positive rate under all conditions tested. Its performance could be further improved by the use of a more stringent definition of a peak requiring the presence of "UP" followed by a "DOWN". The CLUSTER program was found to have very poor sensitivity when using the "local variance" option. Use of the true fixed standard deviation or percent coefficient of variation resulted in a modest improvement. Optimal performance of program CLUSTER was obtained by the use of the best of 3 variance models, testing 12 different cluster sizes (from 1x1 to 4x4) and selecting the best among these: under these conditions it can achieve high sensitivity (90-100%) for very low observed false positive rate, such that its performance was comparable to that of DETECT. The methods developed and illustrated here should permit the definitive characterization and validation of the performance of any one method, the objective comparison of the relative performance of two or more methods for analysis of pulsatile hormone levels for episodic hormone secretion, and lead to the improvement of algorithms for peak detection.

Hormones↗

PubMed2006

Magnetic resonance imaging of arrhythmogenic right ventricular dysplasia: sensitivity, specificity, and observer variability of fat detection versus functional analysis of the right ventricle.

OBJECTIVES: The purpose of this study was to determine interobserver agreement for interpretation of magnetic resonance imaging (MRI) examinations of arrhythmogenic right ventricular dysplasia (ARVD) and to determine sensitivity and specificity of fat detection versus functional parameters measured by MRI. BACKGROUND: The interobserver variability of MRI and the relative importance of different MRI parameters (fat detection, regional and global right ventricular [RV] function) for ARVD diagnosis is unknown. METHODS: Two experienced observers blinded to the clinical history independently analyzed MRI datasets obtained from 40 patients evaluated for ARVD. Twenty normal subjects underwent MRI and served as control subjects. The MRI scans were performed according to a standard protocol on a 1.5-T scanner. The observers reported on fat infiltration, global and regional RV function, myocardial thinning, and chamber dilatation qualitatively. The RV volumes were measured on the cine sequences. RESULTS: Interobserver kappa scores for fat infiltration, global and regional RV function, wall thinning, and RV outflow dilatation were 0.74, 0.94, 0.89, 0.93, and 0.93, respectively. Correlation coefficients between observers for RV end-diastolic volume, end-systolic volume, and ejection fraction were 0.93, 0.94, and 0.95, respectively (p < 0.001). Fifteen patients were diagnosed with ARVD using Task Force criteria. Sensitivity of fat infiltration, RV enlargement, and regional RV dysfunction for diagnosing ARVD was 84%, 68%, and 78%, and specificity was 79%, 96%, and 94%, respectively. CONCLUSIONS: Qualitative assessment of RV structure and function is highly reproducible for experienced observers. Among the qualitative parameters, fat infiltration is less reproducible and lacks specificity compared with RV kinetic abnormalities.

Adipose Tissue↗

PubMed2003

Endogenous phospholipase D2 localizes to the plasma membrane of RBL-2H3 mast cells and can be distinguished from ADP ribosylation factor-stimulated phospholipase D1 activity by its specific sensitivity to oleic acid.

We have examined the specificity of oleate as an activator of phospholipase D2 (PLD2) and whether it can be used to study PLD2 localization and its involvement in cell function. Oleate stimulates PLD activity in intact RBL-2H3 mast cells. Comparing PLD1- with PLD2-overexpressing cells, oleate enhanced PLD activity only in PLD2-overexpressing cells. Membranes were also sensitive to oleate and when membranes prepared from PLD1- and PLD2-overexpressing cells were examined, oleate further increased PLD activity only in membranes from PLD2-overexpressing cells. Overexpressed green fluorescent protein (GFP)-PLD2 fusion protein was localized at the plasma membrane and GFP-PLD1 was found in an intracellular vesicular compartment. Oleate was used to examine whether overexpressed PLD2 co-localized with endogenous PLD2. RBL-2H3 mast cell homogenates were fractionated on a linear sucrose gradient and analysed for both oleate-stimulated activity and ADP ribosylation factor 1-stimulated PLD1 activity. The oleate-stimulated activity co-localized with markers of the plasma membrane including the beta-subunit of the FcepsilonRI and linker for activation of T cells. Fractionation of homogenates from PLD2-overexpressing cells demonstrated that the overexpressed PLD2 fractionated in an identical location to the endogenous oleate-stimulated activity and this activity was greatly enhanced in comparison with control membranes. Examination of membranes prepared from COS-7, Jurkat and HL60 cells indicated a relationship between oleate-stimulated PLD2 activity and PLD2 immunoreactivity. We examined whether oleate could be used to activate secretion and membrane ruffling in adherent RBL-2H3 mast cells. Oleate did not stimulate secretion but did stimulate membrane ruffling, which was short-lived. We conclude that oleic acid is a selective activator of PLD2 and can be used for localization studies, but its use as an activator of PLD2 in intact cells to study function is limited due to toxicity.

ADP-Ribosylation Factors↗

PubMed1996

Sensitivity, specificity, and predictive values of screening tests for eye conditions in a clinic-based population.

PURPOSE: To assess four commonly available visual function tests to detect visually disabling or vision-threatening eye conditions among new patients of a large, urban, public, general ophthalmology clinic. METHODS: Three hundred seventeen patients were tested for contrast sensitivity, Amsler grid abnormalities, and visual acuity at near and at distance. A complete eye evaluation found the prevalence of serious eye diseases, allowing determination of the sensitivity (Sn), specificity (Sp), likelihood ratio (LR), and other characteristics of each test. RESULTS: Of 317 patients, most were Hispanic (77%), women (60%), and middle-aged (44 +/- 17 years). Normal findings were reported in 18%; refractive error in 43%; cataracts in 16%; glaucoma in 7.3%; and macular degeneration in 4.1%. Near visual acuity of 20/40 or worse (Sn = 0.75; Sp = 0.74; LR = 2.8); and distance visual acuity testing of 20/30 or worse (Sn = 0.74; Sp = 0.73; LR = 2.7) correlated significantly with ocular disease, whereas contrast sensitivity testing (Sn = 0.62; Sp = 0.41; LR = 1.1) and Amsler grid test (Sn = 0.19; Sp = 0.92; LR = 2.4) did not. Test performance decreased when refractive errors were excluded and among those younger than 40 years of age relative to those 40 years of age or older. CONCLUSION: Of the four screening tests studied, distance and near threshold visual acuities as defined above were judged to have the best correlations of an abnormal result with ocular disease, both including or excluding refractive error. Different combinations of tests did not result in more accurate detection of ocular disease. More efficient screening tools for detecting ocular disease need to be developed.

Adolescent↗

PubMed1991

Measurement of murine IgG and IgM concentrations in the SCLC MAb panel; effects of concentration on sensitivity and specificity.

Sensitive, solid-phase enzyme immunoassays for detecting murine IgM and IgG were developed and used to quantitate immunoglobulin concentrations in the SCLC MAb panel. Among the IgM MAbs, most contained between 10-75 micrograms ml-1. At least three IgM MAbs, however, contained less than 2 micrograms ml-1 and six contained greater than 75 micrograms ml-1. Two of the three IgM's containing less than 2 micrograms ml-1 immunoglobulin were found to cluster with the negative controls. Among the IgG MAbs, the majority contained between 10-100 micrograms ml-1 Ig. At least five of the IgG MAbs contained greater than 100 micrograms ml-1; and six were less than 2 micrograms ml-1. Three of the MAbs containing less than 2 micrograms ml-1 IgG clustered with the negative controls. Many of the panel members containing greater than 50 micrograms ml-1 antibody were found to give nonspecific immunostaining on tissues and cell lines. Often this nonspecific immunostaining was eliminated when these MAbs were diluted. Although only a minority of the panel members contained very high or very low concentrations of antibody, the data highlight the inherent difficulties that may result, in part from this variable and suggest that efforts be made to normalise the Ig concentrations of panel members in future workshop panels.

Animals↗

PubMed1993

Comparison of fine-needle aspiration biopsy, Doppler ultrasound, and radionuclide scintigraphy in the diagnosis of acute allograft dysfunction in renal transplant recipients: sensitivity, specificity, and cost analysis.

150 episodes of allograft dysfunction in 128 renal transplant recipients, 77 due to acute rejection, 32 secondary to acute-on-chronic rejection, 33 due to either prerenal factors, acute tubular necrosis, or ciclosporin A nephrotoxicity, and 8 secondary to multiple causes, were evaluated by fine-needle aspiration biopsy (FNAB), Doppler ultrasound (DUS), and radionuclide scintigraphy (RS), each performed within a 24-hour period and prior to any specific therapeutic intervention. Tests were interpreted by appropriate specialists in a large transplant center without access to clinical information. The final diagnosis was based primarily upon response to therapeutic maneuvers with histological (core biopsy) confirmation in 123 episodes. RS was the most sensitive (70%) test for the diagnosis of acute rejection during the early posttransplant period, exceeding both FNAB (52%) and DUS (43%). The predictive accuracy of either FNAB, DUS, RS, or core biopsy in the detection of a steroid-responsive component to acute rejection when superimposed upon chronic rejection was low at approximately 50%. When the underlying cause of renal dysfunction was either prerenal, acute tubular necrosis, or ciclosporin A nephrotoxicity, FNAB, DUS, and RS each gave an erroneous diagnosis of acute rejection in about 50% of the episodes. Cost analysis revealed that core biopsy was the most expensive test, but only 9% more than RS, with FNAB the least costly. In conclusion, the lack of ideal sensitivity and specificity combined with the expense of present-day FNAB, DUS, RS, and core biopsy in the diagnosis of a therapeutically reversible component to acute-on-chronic rejection and of FNAB, DUS, and RS in the diagnosis of acute rejection during the early posttransplant period should prompt research into ways to improve their diagnostic yield or alternate modalities.

Acute Disease↗

PubMed1990

Introduction to biostatistics: Part 3, Sensitivity, specificity, predictive value, and hypothesis testing.

Diagnostic tests guide physicians in assessment of clinical disease states, just as statistical tests guide scientists in the testing of scientific hypotheses. Sensitivity and specificity are properties of diagnostic tests and are not predictive of disease in individual patients. Positive and negative predictive values are predictive of disease in patients and are dependent on both the diagnostic test used and the prevalence of disease in the population studied. These concepts are best illustrated by study of a two by two table of possible outcomes of testing, which shows that diagnostic tests may lead to correct or erroneous clinical conclusions. In a similar manner, hypothesis testing may or may not yield correct conclusions. A two by two table of possible outcomes shows that two types of errors in hypothesis testing are possible. One can falsely conclude that a significant difference exists between groups (type I error). The probability of a type I error is alpha. One can falsely conclude that no difference exists between groups (type II error). The probability of a type II error is beta. The consequence and probability of these errors depend on the nature of the research study. Statistical power indicates the ability of a research study to detect a significant difference between populations, when a significant difference truly exists. Power equals 1-beta. Because hypothesis testing yields "yes" or "no" answers, confidence intervals can be calculated to complement the results of hypothesis testing. Finally, just as some abnormal laboratory values can be ignored clinically, some statistical differences may not be relevant clinically.

Biometry↗

PubMedDate not supplied

[Urinary tract infections in newborns: sensitivity, specificity, and predictive value of urinary screening with the reagent strip test].

Important considerations in evaluating newborn urine examinations by dip-stick method are: ease of performance, the volume of the specimen required for test, the time required to perform the test and the cost. In considering the dip-stick test for the early diagnosis of Urinary Tract Infections (U.T.I.), it has never been tested with later follow-up to evaluate its sensitivity and specificity, also in regard to reduce the risk of further complications for urinary tract and kidney.

Carboxylic Ester Hydrolases↗

PubMed1990

Sensitivity, specificity, and predictive values of ClinEase-Virastat saliva test for feline leukemia virus infection.

Detection of virus in saliva using a commercial enzyme-linked immunosorbent assay (ELISA), ClinEase-VirastatR, was compared to evidence of FeLV infection by the indirect immunofluorescent antibody assay (IFA) and plasma ELISA. The sensitivity and specificity of the saliva ELISA were derived by comparison to IFA and plasma ELISA in 103 cats from a large colony in New York State. The sensitivity of the saliva test in relation to IFA and plasma ELISA was approximately 100% and 93%, respectively. The specificity of the saliva ELISA in relation to IFA and plasma ELISA was approximately 85% and 92%, respectively. This test appears to be particularly suitable as a screening test for FeLV infection, especially in populations where the expected prevalence is low. Because of its high sensitivity, the saliva test has a high negative predictive value, particularly in populations where the disease is rare. Since the specificity is moderate, however, the predictive value of a positive test will be poorest in cats originating from places where the infection is rare (e.g. single cat households, or free roaming cats), and better among cats from environments having a high prevalence of FeLV (e.g. multiple-cat households).

Animals↗

PubMed1992

Rapid, sensitive, specific, and quantitative detection of human T-cell leukemia virus type 1 sequence in peripheral blood mononuclear cells by an improved polymerase chain reaction method with nested primers.

Improving on the nested double polymerase chain reaction (PCR) described previously, we have developed a new two-step PCR (TS-PCR) method for detecting more specifically the human T-cell leukemia virus type 1 (HTLV-1) proviral sequences in peripheral blood mononuclear cells (PBMC). In our TS-PCR method, the point of modification is to use optimal concentrations of primers in the first amplification step in the range of 0.01-0.025 microM. This increases sensitivity and specificity enough to detect from 1 to 10(5) copies of template DNA without radioisotopes. This method is rapid because of completion in 1 day and is also applicable for quantitative detection of clinical specimens. The data show that the quantitative detection of HTLV-1 proviral sequences by this method correlates with the anti-HTLV-1 antibody titers from serologic analysis of seropositive healthy carriers. Moreover, the TS-PCR method using each specific primer was also attempted for successful detection of other viral genomes; therefore, the principle of this method is widely suitable for routine detection of genomes in the basic and clinical microbiological fields.

Base Sequence↗

PubMed1988

Cortical evoked potential monitoring during spinal surgery: sensitivity, specificity, reliability, and criteria for alarm.

Cortical somatosensory evoked potentials (EP) were used for intraoperative monitoring of spinal cord integrity during 158 consecutive cases involving surgical correction of spinal deformities. Using a monitoring technique designed to optimize recording, 88% of patients had stable EP results at the time of spinal manipulation. However, five of six patients with preexistent neurological deficits did not have stable EPs. A persistent EP amplitude attenuation of greater than or equal to 40% was a sensitive and specific criterion for alarm. Seven patients had transient attenuations of greater than or equal to 40% after distraction that recovered, so that the distraction instrumentation could be left in place. Overall, this particular cortical somatosensory EP recording technique appears to be appropriate for clinical monitoring. Other recording techniques may be necessary for patients with preexisting neurological deficits.

Adolescent↗

PubMedDate not supplied

Head-up tilt test: a highly sensitive, specific test for children with unexplained syncope.

Unexplained syncope may cause diagnostic and therapeutic problems in children. The head-up tilt test has been shown to be a useful tool for investigating unexplained syncope, especially for diagnosis of neurally mediated syncope. In this study 20 patients aged 9-18 years (12.0 +/- 2.5 years) with syncope of unknown origin and 10 healthy age-matched children were evaluated by head-up tilt to 60 degrees for 25 minutes. The test was considered positive if syncope or presyncope developed in association with hypotension, bradycardia, or both. If tilting alone did not induce symptoms (syncope or presyncope), isoproterenol infusion was administered with increasing doses (0.02-0.08 mu g/kg per minute). During the tilt test, symptoms were elicited in 15 (75%) of the patients with unexplained syncope but in only one (10%) of the control group (p < 0.001). The sensitivity of the test was 75% and its specificity 90%. Three patterns of response to upright tilt were observed in symptomatic patients: vasodepressor pattern with an abrupt fall in blood pressure in 67%; cardioinhibitory pattern with profound bradycardia in 6%; and mixed pattern in 27%. In patients with positive head-up tilt, there were sudden decreases in systolic blood pressure (from 130 +/- 15 to 61 +/- 33 mmHg) and in mean heart rate (from 147 +/- 26 to 90+/-38 beats per minute) (p < 0.001) during symptoms. Treatments with atenolol 25 mg/day has shown complete suppression of syncope in positive responders during a mean follow-up period of 18 +/- 6 months. The head-up tilt test is a noninvasive, sensitive, specific diagnostic tool for evaluating children with unexplained syncope.

Adolescent↗

PubMed2000

Sensitivity, specificity and positive predictive value of patch testing: the more you test, the more you get? ESCD Working Party on Epidemiology.

Pathophysiological variability affects the results of patch testing. In addition, even a minimal degree of test-imprecision due to this variability has a number of important statistical consequences for the analysis and interpretation of any patch test data set. One such statistical phenomenon that is often overlooked is the dependence of the positive predictive value (i.e., the predictive value of a positive patch test) on sensitivity and specificity, the impact of which is heavily dependent on the proportion of truly allergic subjects that are studied. A 2nd important issue is the fact that patch testing is performed in series, which means multiple tests. If we assume, for example, a patch test series of only 10 allergens, then it can be demonstrated that there is a random probability of over 40%) to find, simply by chance, for at least 1 allergen, a statistically significant difference between 2 groups of patients. Comparison of the results of series between patients calls for statistical adjustments in order to prevent erroneously positive differences and/or associations.

Dermatitis, Allergic Contact↗