Kusuma S, et al.
Diagnostic accuracy of clinical.
Diagnostic accuracy of clinical and laboratory tests in scabies: A systematic review Stefanie Kusuma.
Alfin Harjuno Dwiputro Department of Parasitology.
Faculty of Health.
Public Health, and Nursing Universitas Gadjah Mada.
Yogyakarta.
Indonesia https://doi.
org/10.
22146/inajbcs.
ABSTRACT
Submitted: 2026-01-09 Accepted : 2026-04-09 Scabies is a highly contagious parasitic skin disease with significant global morbidity.
Accurate diagnosis is essential for effective treatment and control.
however, clinical manifestations are often nonspecific, and the performance of available diagnostic methods varies considerably.
This systematic review synthesizes evidence on the diagnostic accuracy of clinical and laboratory-based tests for scabies.
It followed PRISMA 2020 guidelines.
A search of PubMed.
Embase, and Web of Science was conducted between 2007 and December 2025 for studies evaluating the diagnostic accuracy of clinical diagnoses.
skin scraping, adhesive tape testing, dermoscopy, and polymerase chain reaction (PCR).
Eligible studies included human participants and reported sensitivity and/or specificity.
Reference standards varied .
linical diagnosis, microscopy, skin scraping, dermoscop.
Two reviewers independently screened studies, extracted data, and assessed quality using QUADAS-2.
When sufficient 2y2 data were available, specificity and predictive values were calculated.
Due to heterogeneity, a narrative synthesis was conducted.
Ten studies .
7Ae2.
involving 1,054 participants across Africa.
Asia.
Europe, and the Middle East were included.
Skin scraping and adhesive tape testing demonstrated consistently high sensitivity, reaching up to 100% in studies using clinical diagnosis as the reference.
Dermoscopy showed variable sensitivity .
Ae86%), influenced by operator expertise and patient factors.
studies with extractable data, dermoscopy versus microscopy yielded a specificity of 95%, with positive and negative predictive values of 84.
0% and 85.
PCR showed high but heterogeneous sensitivity .
Ae100%), with improved performance using standardized sampling.
Specificity reporting was inconsistent, limiting evaluation of false-positive rates.
Skin scraping and adhesive tape testing remain the most sensitive diagnostic methods when mite material is present.
Dermoscopy and PCR are useful complementary tools, though performance varies.
An integrated diagnostic approach is recommended, and findings should be interpreted cautiously due to heterogeneity and variable reference standards.
ABTRAK
Keywords:
diagnostic accuracy.
skin scraping.
PCR.
Skabies merupakan penyakit kulit parasitik yang sangat menular dengan morbiditas global yang signifikan.
Diagnosis yang akurat penting untuk terapi dan pengendalian, namun manifestasi klinis sering tidak spesifik dan akurasi berbagai metode diagnostik masih bervariasi.
Tinjauan sistematis ini bertujuan untuk mempelajari akurasi diagnosis klinis dan metode laboratorium untuk skabies.
Tinjauan sistematis dilakukan sesuai pedoman PRISMA 2020.
Pencarian pada PubMed.
Embase, dan Web of Science dilakukan dalam rentang waktu 2207 hingga Desember 2025 untuk studi yang mengevaluasi akurasi diagnostik dari diagnosis klinis, kerokan kulit, adhesive tape test, dermoskopi, dan polymerase chain reaction (PCR).
Studi yang memenuhi kriteria adalah studi yang melibatkan subjek manusia dan melaporkan sensitivitas dan/atau spesifisitas.
Standar baku bervariasi, termasuk diagnosis klinis, mikroskopi, kerokan kulit, dan dermoskopi.
Dua peneliti secara independen melakukan seleksi studi, ekstraksi data, dan penilaian kualitas menggunakan QUADAS-2.
Penghitungan data 2y2, spesifisitas dan nilai prediktif dihitung jika data tersedia.
Sepuluh studi .
7Ae2.
dengan total 1.
054 partisipan dari Afrika.
Asia.
Eropa, dan Timur Tengah memenuhi kriteria inklusi.
Kerokan kulit dan adhesive tape test menunjukkan sensitivitas tinggi secara konsisten, mencapai hingga 100% pada studi dengan diagnosis klinis sebagai standar baku.
Dermoskopi menunjukkan sensitivitas bervariasi .
Ae86%), dipengaruhi oleh keahlian operator dan faktor pasien.
Pada studi dengan data yang dapat dianalisis, dermoskopi dibandingkan mikroskopi memiliki spesifisitas 80,95%, dengan nilai prediktif positif 84,0% dan negatif 85,0%.
Metode PCR menunjukkan sensitivitas tinggi namun heterogen .
Ae100%), dengan akurasi lebih baik pada teknik pengambilan sampel yang terstandar.
Pelaporan spesifisitas masih Kerokan kulit dan adhesive tape test menjadi metode paling sensitif untuk diagnosis skabies ketika material tungau tersedia.
Dermoskopi dan PCR merupakan metode tambahan yang berguna dalam konteks tertentu, meskipun performanya Pendekatan diagnosis terintegrasi direkomendasikan, dengan interpretasi hasil yang hati-hati mengingat heterogenitas dan variasi standar acuan.
*corresponding author: stefanie.
kusuma@mail.
d@mail.
InaJBCS.
Volume 58.
Number 2, 2026 April:
INTRODUCTION
Scabies is a common and highly contagious parasitic skin infestation caused by Sarcoptes scabiei var.
It remains a major global public health concern, particularly in low-resource and overcrowded settings.
It affects individuals of all ages and is associated with considerable morbidity due to intense pruritus, secondary complications such as post-streptococcal glomerulonephritis and rheumatic heart 2 Beyond individual morbidity, scabies contributes to outbreaks in institutional and community settings, increasing healthcare burden and transmission risk.
3 These clinical and public health impacts highlight the critical importance of accurate and timely diagnosis of scabies.
Scabies is often difficult to diagnose because its clinical manifestations are variable and can resemble other inflammatory or infectious dermatoses, despite its high prevalence.
4 Typical signs such as burrows, papules, and pruritus may be absent or subtle, particularly in early disease, atypical presentations, or patients with low mite burden.
5 Diagnosis based solely on clinical assessment is therefore highly dependent on clinician experience and epidemiological context.
6 Consequently, reliance on clinical features alone may result in misdiagnosis or delayed Several laboratory-based and noninvasive diagnostic methods have been developed and applied in clinical practice to improve diagnostic certainty.
7 Direct microscopic visualization of Sarcoptes scabiei mites, eggs, or fecal pellets obtained by skin scraping or adhesive tape testing is widely regarded as the gold standard for the diagnosis of scabies due to its high specificity.
1 However, this method is limited by operator expertise, sampling technique, and mite burden, which may result in false-negative findings, particularly in early or mild Conventional techniques such as skin scraping and adhesive tape testing rely on direct microscopic visualization of mites or their products, but their sensitivity may be limited by sampling Dermoscopy provides a rapid, noninvasive alternative, while molecular methods such as polymerase chain reaction (PCR) have been introduced to enhance detection, particularly in challenging cases.
9 However, reported diagnostic accuracy varies widely among these methods, leading to uncertainty regarding their optimal use in routine The absence of a universally accepted reference standard and the variability in diagnostic performance reported across studies make a systematic synthesis of the available evidence urgently This systematic review aims to summarize and critically appraise the diagnostic accuracy of clinical diagnosis and laboratory-based tests for scabies, including skin scraping, adhesive tape testing, dermoscopy, and PCR, with emphasis on effect estimates and confidence intervals to inform evidencebased diagnostic strategies.
METHODS
Study design This conducted in accordance with the updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines.
10 The review protocol was developed a priori to ensure methodological transparency, reproducibility, and rigor in synthesizing evidence on the diagnostic accuracy of clinical and laboratory tests for scabies.
The review process followed predefined objectives, eligibility criteria, search strategies, data extraction procedures.
Kusuma S, et al.
Diagnostic accuracy of clinical.
and quality appraisal methods to minimize bias and enhance the reliability of findings.
Literature search strategy A comprehensive literature search was performed in PubMed.
Embase, and Web of Science from database inception to December 2025.
The search strategy combined controlled vocabulary terms (Medical Subject Headings [MeSH] and Emtree term.
and free-text keywords related to Auscabies,Ay AuSarcoptes scabiei,Ay Audiagnosis,Ay Audiagnostic accuracy,Ay Ausensitivity,Ay Auspecificity,Ay Audermoscopy,Ay Auskin scraping,Ay Auadhesive tape test,Ay and Aupolymerase chain reaction.
Ay Boolean operators (AND.
OR) and truncation were applied to optimize search sensitivity and specificity.
No restrictions were placed on publication date or study design.
Searches were limited to studies involving human participants.
The reference lists of included articles and relevant reviews were manually screened to identify additional eligible Detailed search strategies for each database are provided in TABLE 1.
TABLE 1.
Search strategies used for online databases Database Search strategies Records PubMed (AuScabiesAy[Mes.
OR scabies OR AuSarcoptes scabieiAy OR AuSarcoptic scabiesA.
AND ((AuDiagnosisAy[Mes.
OR diagnosis OR diagnostic OR Auclinical diagnosisAy OR rash OR burrows OR pruritus OR itch*) AND (AuSkin TestsAy[Mes.
OR Auadhesive tape testAy OR microscopy OR Auskin scrapingAy OR dermoscopy OR AudermatoscopyAy OR PCR OR Aupolymerase chain reactionAy OR laboratory OR lab OR Aureference standardA.
) AND (AuSensitivity and SpecificityAy[Mes.
OR AuPredictive Value of TestsAy[Mes.
OR AuLikelihood FunctionsAy[Mes.
OR sensitivity OR specificity OR Aupositive predictive valueAy OR Aunegative predictive valueAy OR Aulikelihood ratio*Ay OR accurac.
(AoscabiesAo/exp OR scabies OR Aosarcoptes scabieiA.
AND ((AodiagnosisAo/exp OR diagnosis OR diagnostic OR Aoclinical diagnosisAo OR rash OR burrows OR pruritus OR itch*) AND (Aoskin testAo/exp OR Aoadhesive tape testAo OR microscopy OR Aoskin scrapingAo OR dermoscopy OR dermat* OR PCR OR Aopolymerase chain reactionAo OR laboratory OR lab OR Aoreference standardA.
) AND (AosensitivityAo/exp OR sensitivity OR specificity OR Aopredictive valueAo/exp OR Aopredictive valueAo OR Aopositive predictive valueAo OR Aonegative predictive valueAo OR Aolikelihood ratioAo/exp OR Aolikelihood ratio*Ao OR accuracy OR Aodiagnostic accuracyA.
Medline and EMBASE Web of Science TS=(AuscabiesAy OR AuSarcoptes scabieiA.
AND TS=(AudiagnosisAy OR AudiagnosticAy OR Auclinical diagnosisAy OR rash OR burrows OR pruritus OR itch*) AND TS=(Auskin scrapingAy OR microscopy OR dermoscopy OR dermat* OR PCR OR Auadhesive tape testAy OR Aureference standardAy OR laboratory OR la.
AND TS=(AusensitivityAy OR AuspecificityAy OR Aupositive predictive valueAy OR Aunegative predictive valueAy OR Aulikelihood ratio*Ay OR accuracy OR Audiagnostic accuracyA.
InaJBCS.
Volume 58.
Number 2, 2026 April:
Eligibility criteria Studies were eligible for inclusion if they evaluated the diagnostic accuracy of clinical or laboratory-based tests for scabies in patients of any age with suspected scabies.
Eligible index tests included clinical diagnosis .
presence of rash, burrows, or pruritu.
, skin scraping, adhesive tape testing, dermoscopy, and polymerase chain reaction (PCR).
Reference standards included clinical diagnosis, microscopy, skin scraping, dermoscopy, or other Studies were required to report at least one diagnostic accuracy outcome, such as sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios, or sufficient data to calculate these measures, preferably with 95% confidence intervals.
Eligible study designs included prospective or retrospective diagnostic accuracy studies and cross-sectional studies.
Studies were excluded if they were animal or laboratory-only studies, review articles, conference abstracts without full text, editorials, opinion papers, or if they lacked sufficient data to assess diagnostic Study selection and data extraction All retrieved records were imported into reference management software, and duplicate entries were removed prior to screening.
Two independent reviewers screened titles and abstracts, followed by a full-text review of potentially eligible Discrepancies were resolved through discussion or consultation with a third reviewer when necessary.
Data extraction was performed independently using a standardized data extraction Extracted information included author, publication year, country, study design, sample size, participant characteristics, index test.
, reference standard.
, and reported diagnostic accuracy outcomes, including effect estimates and 95% confidence intervals where available.
Methodological quality and risk of bias of the included studies were assessed independently by two reviewers using QUADAS-2 domainbased judgments .
atient selection, index test, reference standard, and flow and timin.
For each domain, signaling questions were used to guide judgments as low, high, or unclear risk of bias, and applicability concerns were considered High-risk judgments were assigned particularly when the reference standard was non-independent from the index test, when incorporation of clinical judgment or dermoscopy into the reference standard was evident, or when flow and timing were insufficiently Disagreements were resolved by consensus.
When studies provided sufficient raw 2y2 data, additional diagnostic accuracy measures such as specificity, positive predictive value, and negative predictive value were The results of the quality appraisal are summarized in TABLE 2.
Kusuma S, et al.
Diagnostic accuracy of clinical.
TABLE 2.
Quality assessment and risk of bias of included studies Study (Yea.
Patient Selection Index Test Reference Standard Flow & Timing Applicability Concerns Abdel-Latif et al.
,11
Low Low High Low Low Bae et al.
Low Low Low Low Low Chung et al.
,13
Low Low Low Low Low Delaunay et al.
,14
Low Low High Low Low Low Low Low Low Low Dupuy et al.
Enechukwu et al.
Low Low Low Low Low Low Low Low Low Low Walter et al.
Low Low High Low Low Low Low Low Low Low Low Low Low Low Low Hahm et al.
Wong et al.
Zorbozan et al.
Note: QUADAS-2 judgments were guided by explicit signaling-question criteria.
Patient selection was considered high risk when clearly non-consecutive or case-control sampling was used.
index test was considered high risk when interpretation was not independent of the reference standard or thresholds were applied post hoc.
reference standard was considered high risk when clinical diagnosis or dermoscopy formed part of the confirmation process without independent verification.
and flow and timing was considered high risk when not all participants underwent the same reference standard or when timing was Data synthesis A quantitative meta-analysis was not performed due to substantial heterogeneity among the included studies in terms of study design, index tests, reference standards, and reported diagnostic accuracy measures.
Instead, a narrative synthesis was conducted.
Diagnostic accuracy outcomes were summarized descriptively by test modality, with particular emphasis on effect estimates and 95% confidence Variations in diagnostic performance were explored in relation to study setting, patient population, sampling technique, and reference RESULTS Study selection The systematic database search identified a total of 3,674 records from PubMed .
= 1,.
Embase .
= 1,.
, and Web of Science .
= 1,.
After removing 1,602 duplicate records, 2,072 unique articles remained for title and abstract screening.
Of these, 1,912 articles were excluded as they were not relevant to scabies diagnosis or did not assess diagnostic accuracy.
A total of 160 fulltext articles were sought for retrieval, of which 8 articles were not accessible.
Consequently, 152 full-text articles were assessed for eligibility.
After full-text review, 142 studies were excluded for the following reasons: inappropriate index test or reference standard .
= .
, absence of diagnostic accuracy outcomes .
= .
, conference abstracts or review articles .
= .
, and nonEnglish publications .
= .
Ultimately, 10 studies published between 2007 and 2025 met the inclusion criteria and were included in this systematic review.
The study selection process is illustrated in FIGURE 1.
InaJBCS.
Volume 58.
Number 2, 2026 April:
Screening Identification Identification of studies through databases Articles identified from database searching (N =3.
1311 PubMed 1240 Embase 1123 Web of Science Records removed before screening due to duplication in EndNote (N =1.
Articles for title/abstracts screening (N = 2.
Articles excluded from Title & Abstract screening (N =1.
Articles sought for retrieval (N = .
Reports not retrieved (N =.
Articles excluded (N=.
The exposure or interest was not reported (N=.
The outcome or interest was not reported (N=.
Conference abstract or review (N=.
Non-english study (N=.
Included Articles assessed for eligibility (N = .
Full text articles included to the systematic review (N =.
FIGURE 1 Study characteristics The 10 included studies were conducted across Africa .
= .
Asia .
= .
Europe .
= .
, and the Middle East .
= .
, demonstrating broad geographical All studies included patients of all ages with suspected scabies, recruited from dermatology clinics, hospitals, or community-based Sample sizes ranged from 42 to 245 participants, with a total pooled sample of 1,054 individuals.
The evaluated diagnostic modalities included skin scraping .
= 3 studie.
, adhesive tape test .
= .
, dermoscopy .
= .
, and polymerase chain reaction (PCR) .
= Several studies assessed more than one diagnostic test.
Reference standards varied across studies and included clinical diagnosis, microscopy, skin scraping, and dermoscopy.
Diagnostic accuracy outcomes were primarily reported as sensitivity, with fewer studies reporting specificity or predictive values.
Regarding risk of bias, patient selection and index test domains were generally judged as low risk, whereas three studies were judged as high risk in the reference standard domain because the reference standard incorporated clinical diagnosis or dermoscopy without clear independent confirmation.
A detailed summary of study characteristics is provided in TABLE 3.
Diagnostic accuracy of skin scraping and adhesive tape tests Three studies evaluated skin scraping as a diagnostic method for scabies.
AbdelLatif et al.
,11 reported a sensitivity of Kusuma S, et al.
Diagnostic accuracy of clinical.
100% .
% CI: 95.
26Ae100.
in a cohort of 100 patients using clinical diagnosis as the reference standard.
Similarly.
Walter et al.
,18 reported a sensitivity of 100% .
% CI: 94.
00Ae100.
among 113 Zorbozan et al.
,20 comparing skin scraping with superficial skin biopsy, demonstrated strong agreement between the two methods, supporting the reliability of skin scraping as a laboratory diagnostic tool.
Two studies evaluated the adhesive tape test.
AbdelLatif et al.
,11 reported a sensitivity of 100% .
% CI: 95.
70Ae100.
, while Walter et ,18 again observed a sensitivity of 100% .
% CI: 94.
00Ae100.
Across studies, both skin scraping and adhesive tape testing consistently demonstrated very high sensitivity.
TABLE 3.
Characteristics of studies that included in systematic review Author Year Subgroup Country Title Total Sample Size Test Name Confirmation of Scabies Journal Abdel-Latif et al.
,11
All age Egypt Comparing the diagnostic properties of skin scraping, adhesive tape, and dermoscopy in diagnosing Skin scraping.
Adhesive Tape.
Dermoscopy Clinical Diagnosis Acta Dermatovenerol Bae et al.
,12
All age Republic of Korea Diagnostic value of the molecular detection of Sarcoptes scabiei from a skin scraping in patients with suspected scabies PCR Microscopy PLoS Negl Trop Dis Chung et al.
,13
All age Republic of Korea Standardized cotton swab sampling with nested quantitative polymerase chain reaction is effective for diagnosing ordinary PCR Microscopy Clin Exp Dermatol Delaunay et al.
,14
All age France Scabies polymerase chain reaction with standardized dry swab sampling: an easy tool for cluster diagnosis of human scabies PCR Dermoscopy Br J Dermatol Dupuy et al.
,15
All age France Accuracy of standard dermoscopy for diagnosing Dermoscopy Skin scraping J Am Acad Dermatol Enechukwu et al.
,16
All age Nigreria Assessing the accuracy of dermoscopy for scabies diagnosis in dark African Dermoscopy Microscopy Dermatol Pract Concept Hahm et al.
,17
All age Korea The efficacy of a nested polymerase chain reaction in detecting the cytochrome c oxidase subunit 1 gene of Sarcoptes scabiei var.
hominis for diagnosing scabies PCR Microscopy Br J Dermatol Walter et al.
,18
All age Germany Comparison of dermoscopy, skin scraping, and the adhesive tape test for the diagnosis of scabies in a resource-poor setting Skin scraping.
Adhesive Tape.
Dermoscopy Clinical Diagnosis Arch Dermatol Wong et al.
,19
All age Hong Kong Development of Conventional and RealTime Quantitative PCR Assays for Diagnosis and Monitoring of Scabies PCR Microscopy J Clin Microbiol Zorbozan et al.
,20
All age Turkey Comparison of Skin Scraping and Standard Superficial Skin Biopsy in the Laboratory Diagnosis of Scabies Skin scraping Skin scraping Turkiye Parazitol Derg TABLE 4.
2y2 contingency TABLE for dermoscopy vs microscopy Dermoscopy Result Microscopy Positive Microscopy Negative Positive Negative InaJBCS.
Volume 58.
Number 2, 2026 April:
Diagnostic accuracy of dermoscopy Four studies assessed dermoscopy for the diagnosis of scabies, with reported sensitivities ranging from 46.
0% to 86.
Abdel-Latif et al.
,11 reported a sensitivity 41% .
% CI: 74.
36Ae91.
, while Dupuy et al.
,15 reported a sensitivity 00% .
% CI: 80.
00Ae92.
Walter et al.
,18 reported a substantially lower sensitivity of 46.
% CI: 34.
00Ae58.
Enechukwu et ,16 highlighted diagnostic challenges when using dermoscopy in individuals with darker skin tones, which may In the study that provided a complete 2y2 TABLE, dermoscopy versus microscopy yielded a specificity 95% .
, a positive predictive value of 84.
0% .
, and a negative predictive value of 85.
0% .
Overall, dermoscopy demonstrated moderate to high sensitivity, but with considerable variability across studies, likely reflecting differences in operator expertise, patient populations, and reference standards.
Diagnostic accuracy of polymerase chain reaction (PCR) Five studies evaluated PCR-based diagnostic methods for scabies.
Sensitivity estimates ranged from 74.
29% to 100%.
Delaunay et al.
,14 reported a sensitivity of 100% .
% CI 95.
32Ae100.
using standardized dry swab sampling and dermoscopy as the reference standard.
Bae et al.
,12 also reported a sensitivity of 100% .
% CI 80.
00Ae100.
, while Wong et al.
,19 reported a sensitivity of 86.
% CI 76.
11Ae92.
Hahm et al.
,17
observed lower sensitivity at 74.
% CI 56.
74Ae87.
, particularly in cases with low mite burden.
DISCUSSION
This systematic review synthesized evidence from ten studies published between 2007 and 2025 evaluating the diagnostic accuracy of clinical and laboratory-based tests for scabies.
The included studies encompassed a range of study designs, including prospective diagnostic accuracy studies and crosectional clinical evaluations, reflecting real-world diagnostic practices across diverse healthcare settings.
Collectively, the evidence highlights substantial variability in diagnostic performance across modalities, with skin scraping and adhesive tape testing demonstrating consistently high sensitivity, while chain reaction (PCR) showed more heterogeneous results depending on context, reference standards, and patient Skin scraping and adhesive tape testing, overall, demonstrated the most consistently high sensitivity, with several studies reporting sensitivities of 100% and narrow confidence intervals.
These findings are consistent with previous diagnostic reviews and guideline-based evidence, which have long recognized direct visualization of mites, eggs, or fecal pellets as the most definitive method for confirming scabies infection.
21,22
Although skin scraping and adhesive tape testing consistently demonstrated high reported sensitivity, these findings should not be interpreted as definitive evidence of diagnostic superiority.
The high sensitivity observed in these studies likely reflects both careful lesion selection and operator expertise, as sampling from active burrows or papules increases the likelihood of detecting mite material.
23 Nevertheless, false-negative results may still occur in early infestations, cases with low mite burden, or following partial treatment, underscoring that even highly sensitive visualization-based methods are not 24 Despite these limitations, the reproducibility of high sensitivity across multiple studies supports the continued role of skin scraping and adhesive tape testing as reference or confirmatory diagnostic tools in both clinical practice Kusuma S, et al.
Diagnostic accuracy of clinical.
and research settings.
Dermoscopy, in contrast, showed accuracy, with reported sensitivities ranging from 46% to 86%, a pattern that has also been observed in previous studies and narrative reviews.
25,26
Higher diagnostic yields were typically reported in specialized dermatology settings, whereas lower sensitivity was observed in primary care or resourcelimited environments.
27 This variability likely reflects the operator-dependent nature of dermoscopy, as accurate interpretation requires familiarity with characteristic scabies features such as the Audelta wing jetAy sign.
28 Furthermore, patient-related skin pigmentation, lesion chronicity, excoriation, and secondary infection, may obscure dermoscopic features, particularly in populations with darker skin tones, thereby reducing diagnostic 29 These findings highlight that dermoscopy is a valuable adjunctive tool but should not be used in isolation without adequate training and clinical PCR-based demonstrated generally high sensitivity, ranging from 74% to 100%, suggesting strong potential as a diagnostic adjunct, particularly in cases with low mite burden or equivocal clinical findings.
Similar results have been reported in earlier molecular diagnostic studies, which showed that PCR can detect Sarcoptes scabiei DNA even when microscopy Higher standardized sampling techniques, such as dry swab or cotton swab collection, emphasizing the importance of specimen collection and handling.
31,32 However, variability in PCR targets, amplification protocols, and reference standards limited direct comparability across Additionally, the requirement for laboratory infrastructure, technical expertise, and higher costs may restrict the widespread implementation of PCR in low-resource settings, where scabies prevalence is often highest.
Several limitations of the available evidence should be acknowledged.
First, reference standards varied substantially diagnosis, microscopy, skin scraping, and dermoscopy, which may have introduced verification bias and influenced reported accuracy estimates.
Second, most studies primarily reported sensitivity, and only a small minority provided sufficient raw data to derive specificity, predictive values, or likelihood ratios, restricting comprehensive evaluation of diagnostic Third, differences in study design, patient populations, disease severity, and operator expertise contributed to heterogeneity and precluded quantitative meta-analysis.
Fourth, most studies were conducted in single-center settings, potentially limiting generalizability.
A major limitation of the included studies is the use of heterogeneous and, in some cases, non-independent reference standards.
Finally, publication bias cannot be excluded, as studies performance may be more likely to be Despite these limitations, this review provides a comprehensive synthesis of current evidence on scabies diagnostic methods and highlights important gaps for future research.
Standardization of reference standards, improved reporting of full diagnostic accuracy metrics, and evaluation of diagnostic algorithms combining clinical and laboratory tools are needed.
Interpretation of the findings should limitations in the underlying literature.
Several included studies used imperfect non-independent standards, introducing incorporation and verification bias.
A further limitation of the included literature is the presence of circular validation arising from the InaJBCS.
Volume 58.
Number 2, 2026 April:
use of hierarchical but non-independent reference standards.
Further studies assessing feasibility, cost-effectiveness, and implementation in endemic and resource-limited settings will be essential to inform evidence-based diagnostic CONCLUSION This systematic review indicates that skin scraping and adhesive tape tests are associated with the highest reported sensitivity for scabies diagnosis when mite material is present.
However, the true diagnostic accuracy of these methods remains uncertain due to heterogeneity in study design, variability standards, and limited reporting of Dermoscopy and polymerase chain reaction (PCR) may serve as useful complementary diagnostic tools, although their performance varies across clinical settings, reference standards, and patient populations.
Where raw data were available, dermoscopy also showed moderate specificity, but such reporting was uncommon across the included studies.
Overall, these findings underscore the need for cautious interpretation of existing accuracy estimates and support an integrated diagnostic approach that combines clinical assessment with appropriate confirmatory tests, tailored to available resources and expertise.
REFERENCES