Search

Background/Aim. Bacterial vaginosis (BV) is a common cause of vaginal discomfort in women. The aim of this study was to compare Nugent?s scoring system and novel microscopy method, introduced in our laboratory and used in BV diagnosis. Methods. This study included 705 pregnant and asymptomatic women between 24 and 28 weeks of pregnancy. The degree of agreement between methods was determined by the kappa (?) index. The sensitivity, specificity, positive and negative predictive value of the novel microscopy method was compared to Nugent?s score as standard. Results. Based on the scoring system of both methods, Nugent?s and novel microscopy method, BV was diagnosed in 21% and 25% of women, respectively. Despite the disparities among diagnostic criteria, which mainly concerned classification of intermediary samples, the degree of agreement between categories, determined by ? index, was satisfactory: Nugent?s vs. novel microscopy method (? = 0.68; good agreement), and Nugent?s vs. novel microscopy method without intermediary results (? = 0.83; very good agreement). We also demonstrated that compared to Nugent?s method, as the golden standard, the novel microscopy method had high sensitivity and specificity (ranging from 75%?99.3%) and positive and negative predictive values (ranging from 88.8%?99.5%). Our method is based on a relative number of bacterial morphotypes, either rod forms (? 1.5 ?m, lactobacilli) or non-rod forms (< 1.5 ?m, bacterial vaginosis associated bacteria) under 200? magnification, which extends the surface of examined preparation, but without prolongation of observer?s working time. Conclusion. The novel microscopy method in diagnosing BV corresponded well with Nugent?s scoring system which allows it to be an alternative method in diagnosing BV. Further-more, the novel microscopy method is based on a relative number of bacterial morphotypes that appeared to be flexible and can be reorganized in the way to categorize findings into only two groups: normal and BV, which makes it comparable to dichotomous Amsel?s clinical criterion.

Background Age estimation is an important factor in forensic science for human identification. Teeth are considered to play a vital role as they resist decomposition at death unlike other tissues. This resistance and the gradual structural changes that take place throughout the life of an individual have made teeth useful indicators for age estimation. Dental cementum shows continuous apposition throughout the life of an individual. Tooth cemental annulation is a microscopic method for the determination of an individual’s age based on the analysis of incremental lines of cementum. Light microscopy as well as specialized microscopic methods have been employed to enhance the assessment of the cemental annulations. Periodontal disease is the most common dental problem affecting millions of people. Assessing the efficiency of the tooth cemental annulations method in periodontally diseased teeth is an important requisite. This study aims at assessing and evaluating the tooth cemental annulations in normal and periodontally diseased teeth using phase contrast microscopic method for age determination. Results A total of 60 teeth were included in the study and out of which 30 teeth were normal (sound teeth without any associated pathologies) and 30 were periodontally involved teeth respectively. Longitudinal ground sections were prepared and observed under phase contrast microscope. Measurements were made using an image analyzer software. The total width of the cementum was divided by the distance between two incremental lines. The eruption age of the tooth was then added to this to obtain the chronologic age for each individual. The results in the present study showed that tooth cemental annulations are applicable to periodontally sound teeth as well as in periodontally diseased teeth. There was no significant difference of estimated age from the actual age in both periodontally sound and periodontally diseased teeth. Normal teeth showed a reliability value of 92% and periodontally compromised teeth showed 96% respectively. There was no substantial influence of periodontal health on the estimated age. Conclusions The study concludes that the use of phase contrast microscopy in conjunction with image enhancement procedures improves the accuracy of age estimation and may serve as a reliable aid in forensic identification.

Cystoisospora belli (C. belli) is the only pathogenic species of the Cystoisospora genus responsible for severe diarrhea in immunocompromised patients. Most common microscopic method of diagnosis is less sensitive due to intermittent shedding of oocysts. We developed a new single-run polymerase chain reaction (PCR)–based diagnostic assay for C. belli. A new single-run PCR-based diagnostic assay was standardized for the detection of C. belli. Diagnostic reproducibility and repeatability of the PCR assay were evaluated. A cross-sectional analytical study was done on a total of 354 stool samples collected from 331 immunocompromised patients with diarrhea. All the stool samples were tested for the presence of oocysts of C. belli and were also tested by our new PCR assay for C. belli. Three of the representative PCR products were confirmed by sequencing. Fisher’s exact test was used to compare the two proportions. Microscopy detected C. belli in 11/354 (3.1%) of stool samples, and the new PCR-based assay detected C. belli in 16/354 (4.5%). The new single-run PCR-based assay detected C. belli in all the stool samples which were tested positive by microscopy and additionally detected C. belli in five stool samples. The developed PCR assay detected statistically significant proportion of C. belli (p < 0.001) as compared to microscopy. The 795 base pair PCR product from one microscopy positive stool sample and two microscopy negative stool samples were confirmed by sequencing. Our newly developed single-run PCR-based detection assay for C. belli is robust and reproducible. It may be used for molecular diagnosis of cystoisosporiasis especially in transplant, pediatrics, and human immunodeficiency virus (HIV) positive patients.

Thickness of the cotton fiber wall or fiber maturity is an important property affecting fiber quality, yield, and textile performance. Due to the complexity of within-sample variation, mean values alone are not sufficient to evaluate cotton maturity. Distributional parameters should be examined for accurately evaluating cotton maturity variations within a sample. However, maturity distributions have not been well characterized due to difficulties of determining maturity from individual fibers with lengthy and laborious microscopic techniques. Cottonscope was developed recently as an alternative for efficiently measuring fiber maturity by analyzing 20,000 snippets from a cotton sample. Thus, we investigated if Cottonscope enabled assessing maturity distributions as accurately as the microscopic method. Maturity distributions determined by Cottonscope were closer to normal distribution curves as compared with those determined by a microscopic method. By comparing maturity with chemical compositions of developing fibers at various stages, a new maturity threshold of the severely immature fibers was selected. Using this threshold, a distributional parameter, immature fiber content (IFC) was measured by both Cottonscope and microscopic methods from cotton reference materials composed of a broad maturity range. The Cottonscope IFC was strongly and significantly correlated with the IFC measured by the microscopic method. It also enabled distinguishing maturity variations from the cotton samples sharing an identical mean maturity. Therefore, the distributional parameter may be used to improve the ways of evaluating the within-sample maturity variation and detecting differences of fiber maturity distributions among cotton samples.

The success of the anti-helminth mass treatment use Albendazole makes detection of soil transmitted helminth infections even more difficult to do microscopically. It is hoped that the molecular method was able to help increase the detectability of Soil Transmitted Helminth infection. The research aimed is to evaluate effectiveness of Albendazole administration in Bali, to identify the presence of β-tubulin gene as molecular diagnosis of STHs infection among children who treated by Albendazole. This study is a cross-sectional study that recruits elementary school children aged 6-12 years as subjects. Stool examination was carried out using the Kato-Katz technique, then followed by a molecular method using the B-tubulin gene as the target gene. The results showed that only 1 sample out of 140 examined using Kato-Katz was positive for Trichuris trichiura. 30 samples were then extracted from the faeces and performed Polymerase Chain Reaction. A total of 4 positive samples detected the B-tubulin Ascaris lumbricoides gene and 1 positive sample of the B-tubulin Trichuris trichiura gene. In conclusion, albendazole is still effective to treat STH infection, the molecular method has a higher detectability than the microscopic method.

Introduction: Anterior odontoid screw fixation technique for specific types of odontoid fracture has been proven to be an effective, yet challenging procedure because of threatened damage to the structures in the vicinity. There are few articles suggesting the role of percutaneous and endoscopic technique as an alternative approach to the standard microscopic way. This is the first cadaveric study using existing “EASY GO” endoscopic system-assisted odontoid screw placement. Study Design: This was a cadaveric study. Objective: The objective of the study is to use the endoscope as a safer minimally invasive approach than the standard microscopic anterior approach to odontoid. Methodology: This is a pilot study on 10 fresh-frozen formalin-fixed adult human cadavers. The cadaver was positioned in a way to simulate reduced odontoid fracture. Tubular dilators were used to dock at C2–3 disk space after identifying the landmarks through the microscopic method. The EASY GO endoscopic system was then introduced, and a handheld drill was used to mark the entry point and pass the K-wire through the planned trajectory. Results: No vascular or adjacent vital structures' injury was observed in any of the cadavers. The initial difficulty in attaining the alignment was overcome by the appropriate positioning of the scope. Conclusions: Endoscopic-assisted technique for odontoid screw fixation shall provide a minimally invasive, safe, and easy surgery.

Objective: To study thrombocytopenia and elevated ALT levels in malaria patients reporting to Pak Med Level II+ Hospital XII and XIII, UN Mission Liberia, West Africa. Study Design: Cross sectional study. Place and Duration of Study: Departments of Pathology and Medicine, Pak Med Level II+ Hospital XII and XIII, UN Mission Liberia, West Africa, from Feb 2015 to Dec 2016. Methodology: In total of 100 febrile patients of both gender and all ages reported to Pak Med Level II+ Hospital XII and XIII, Liberia with clinical features of malaria and having positive malarial parasite (MP) on any of the methods of immune chromatography (ICT) or microscopic film were included. The febrile patients with typical clinical features of malaria but having negative MP both on ICT and microscopic methods were excluded.Pretreatment whole blood in EDTA was collected for testing MP on ICT and by microscopic method including MP index and platelets, while serum for ALT. Results: Out of total 100 patients, 75 were males, 25 females with mean age of 38 ± 5 years. MP was found positive on MP film in 95% and on ICT in 88% cases. Thrombocytopenia was found in 69% and ALT was elevated in 60% cases. Mean and SD for platelets count was 129 ± 72 x 109/L and of ALT 76 ± 66 U/L. Mean of MP index was 0.49 ranging from 0 to 3.5%. Correlation of MP index with platelets and ALT was found insignificant, although in malaria patients, platelets and ALT was inversely correlated significantly with each other showing low platelets along with elevated ALT levels. Conclusion: In malaria patients, thrombocytopenia and elevated ALT are frequent findings, which may not definitely correlate with MP index. So it is advisable to test for platelet count and ALT in all patients of malaria for early diagnosis and better management.

Plasmodium ovale is a benign tertian malaria parasite that morphologically resembles Plasmodium vivax. P. ovale also shares similar tertian periodicity and can cause relapse in patients without a radical cure, making it easily misidentified as P. vivax in routine diagnosis. Therefore, its prevalence might be underreported worldwide. The present study aimed to quantify the prevalence of P. ovale misidentified as P. vivax malaria using data from studies reporting confirmed P. ovale cases by molecular methods. Studies reporting the misidentification of P. ovale as P. vivax malaria were identified from three databases, MEDLINE, Web of Science, and Scopus, without language restrictions, but the publication date was restricted to 1993 and 2020. The quality of the included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS). The random-effects model was used to estimate the pooled prevalence of the misidentification of P. ovale as P. vivax malaria by the microscopic method when compared to those with the reference polymerase chain reaction method. Subgroup analysis of participants was also performed to demonstrate the difference between imported and indigenous P. ovale cases. The heterogeneity of the included studies was assessed using Cochran's Q and I2 statistics. Publication bias across the included studies was assessed using the funnel plot and Egger’s test, and if required, contour-enhanced funnel plots were used to identify the source(s) of funnel plot asymmetry. Of 641 articles retrieved from databases, 22 articles met the eligibility criteria and were included in the present study. Of the 8,297 malaria-positive cases identified by the PCR method, 453 P. ovale cases were confirmed. The pooled prevalence of misidentification of P. ovale as P. vivax malaria by the microscopic method was 11% (95% CI: 7–14%, I2: 25.46%). Subgroup analysis of the participants demonstrated a higher prevalence of misidentification in indigenous cases (13%, 95% CI: 6–21%, I2: 27.8%) than in imported cases (10%, 95% CI: 6–14%, I2: 24.1%). The pooled prevalence of misidentification of P. vivax as P. ovale malaria by the microscopic method was 1%, without heterogeneity (95% CI: 0–3%, I2: 16.8%). PCR was more sensitive in identifying P. ovale cases than the microscopic method (p 2: 65%). Subgroup analysis of participants demonstrated the better performance of PCR in detecting P. ovale malaria in indigenous cases (p: 0.0009, OR: 6.92, 95% CI: 2.21–21.7%, I2: 68%) than in imported cases (p: 0.0004, OR: 2.15, 95% CI: 1.41–3.29%, I2: 63%). P. ovale infections misidentified as P. vivax malaria by the microscopic method were frequent and led to underreported P. ovale cases. The molecular identification of P. ovale malaria in endemic areas is needed because a higher rate of P. ovale misidentification was found in endemic or indigenous cases than in imported cases. In addition, updated courses, enhanced training, and refreshers for microscopic examinations, particularly for P. ovale identification, are necessary to improve the microscopic identification of Plasmodium species in rural health centres where PCR is unavailable.

Objective: This study aimed to inspect the occurrence of Haemoproteus tinnunculi (H. tinnunculi) in falcons from the central area of Saudi Arabia. Materials and Methods: Blood samples from 100 falcons species, including 55 Falco cherrug, 22 Falco peregrinus, 13 Falco pelegrinoides, and 10 Falco rusticolus, were collected from November 2018 to April 2019 and examined for H. tinnunculi by microscopic examination and nested PCR, targeting a cytochrome b (cytb) gene. Results: The prevalence was 1% by microscopic examination. The prevalence rate of H. tinnunculi was 1% by the microscopic method and 3% by PCR. Only F. cherrug was infected. In the sequence and phylogenetic analyses, the two cytb H. tinnunculi sequences were 100% identical and closely related to the Lithuanian isolate with 99.35% identity. Conclusions: This study presents the first report of molecular detection and characterization of H. tinnunculai in F. cherrug from the Kingdom of Saudi Arabia. [J Adv Vet Anim Res 2020; 7(4.000): 626-632]

Sarcocystis is considered as a common zoonotic coccidian parasite that infects intermediate hosts orally through ingestion of contaminated graze or water with protozoa oocyte. The purpose of study is to demonstrate the incidence of Sarcocystis infection in imported cattle in Duhok abattoir and achieve the gold conventional method for muscular tissue cyst and bradyzoites detection. Muscular tissue samples have been collected from esophagus, heart and diaphragm of 150 cattle. From a total of 1350 inspected samples (diaphragm, esophagus and heart) from three different imported origin have been 94%, 92% and 41.3% samples infected respectively as well as significant differences (p

In the academic year of 2019, the designed personalized learning and assessment was applied to the fourth-year pharmacy students who registered for the Pharmacognosy Laboratory in the Faculty of Ph...

Mycobacterium tuberculosis is a cause of tuberculosis (TB ) disease. In this research Mycobacterium tuberculosis can be detected using the Microscopic and Real-Time PCR. This research aims are to know the difference in the results of the examination Mycobacterium tuberculosis with microscopic method and Real-Time PCR. This research used an experimental research design and was tested using the Chi Square test. This results showed at significant difference (p=0.000) detection of pulmonary TB disease by microscopic and Real-Time PCR methods

When considering methods of detecting Cryptosporidium in patient samples, clinical and public health laboratories have historically relied primarily on microscopy. However, microscopy is time intensive and requires trained personnel to accurately identify pathogens that are present. Even with skilled analysts, the parasitemia level has the potential to fall below the level of detection. In addition, public health laboratories do not always receive specimens in fixatives that are compatible with the desired microscopic method. Antigen-based and molecular methods have proven to be effective at identifying Cryptosporidium at low levels and require less training and hands-on time. Here, we have developed and validated a real-time polymerase chain reaction (RT-PCR) laboratory-developed test (LDT) that identifies Cryptosporidium hominis and Cryptosporidium parvum, and also includes detection at the genus level to identify additional species that occasionally cause disease in humans. Results of the molecular test were compared with those obtained from modified acid-fast microscopy, immunofluorescent microscopy, an antigen-based detection rapid test, and a commercial gastrointestinal panel (GI panel). Of 40 positive samples, microscopy and antigen-based methods were able to detect Cryptosporidium in only 20 and 21 samples, respectively. The GI panel detected 33 of the 40 positive samples, even though not all specimens were received in the recommended preservative. The LDT detected Cryptosporidium in all 40 positive samples. When comparing each method for the detection of Cryptosporidium, our results indicate the LDT is an accurate, reliable, and cost-effective method for a clinical public health reference laboratory.

The three-dimensional structures of polymer membranes are different at surfaces and inside bulks, and thus, in general, physical/chemical properties are also different. Morphologies and properties of membrane surfaces are now visualized by current-sensing atomic force microscopy. The increase in performances of a single cell is discussed based on the three-dimensional structures of the polymer membrane, anion-exchange membrane as an example, used for fuel cells. Other reports on Nafion®, proton-exchange membrane, are also introduced to show the importance of this microscopic method.

Issues related to the reproduction of animals have been and remain one of the most complex and relevant problems of biology and are constantly finding a direct and effective way out into livestock farming practice. The rational use of breeding sheep as producers is limited by the lack of standard, objective methods and methods for the timely assessment of their reproductive ability. The article presents the results of evaluating the sperm production of rams-producers. For the first time, the freshly obtained sperm of rams of Moldavian type producers of the Karakul breed was evaluated using the macroscopic method - ejaculate volume, color and smell, as well as the microscopic method - motility, sperm concentration in the ejaculate, total sperm count in the ejaculate sperm movements (VAP; VSL and VCL) as well as the percentage of abnormal forms of sperm. The experiments were carried out on sheep producers grown on a pedigree farm of the experimental farm of the Moldavian Scientific and Practical Institute of Biotechnology in Animal Husbandry and Veterinary Medicine. As a result of the studies, it was found that the ejaculate volume on average was 0.99 ± 0.04 ml, motility was 0.95 ± 0.02 and sperm concentration 1.51 ± 0.14 billion/ml. The percentage of pathological forms in sperm averaged 13.72 ± 0.61, an indicator that characterizes the high quality of sperm. The average quality indicator of ejaculates obtained from ram-producers of the Moldavian type of the Karakul breed corresponds to physiological standards for the Karakul breed. The average percentage of pathological forms of sperm found in ejaculates indicates that the rams were in good conditions of feeding and keeping. According to research, we can say that the Moldovan type of Karakul rams can be successfully used to obtain high quality ejaculates suitable for freezing sperm at 196°C.

Mycoplasma suis (M. suis) is an haemotropic Mycoplasma that adheres and invades erythrocytes and is responsible for infectious anaemia of pigs. Infections with M. suis have been reported worldwide. Clinical signs after M. suis infection can be significant particularly for the breeding herd in the period around farrowing but consequences are highly variable with some infected pigs never exhibiting clinical disease. The study aimed to determine the clinical relevance of Giemsa-stained blood smear for the diagnosis of M. suis compared with qPCR results. In our study, the comparison of qPCR results with microscopic investigation of Giemsa-stained blood smears revealed a lower sensitivity of the microscopic method: only 33 out of 102 qPCR positive blood samples were microscopically positive (M. suis visualised). No relationship between mean qPCR loads and microscopic observation was observed. Although more costly, qPCR is probably the best diagnostic tool available today for M. suis diagnosis.

Aim: To compare the effectiveness of endoscopic v/s microscopic excision of a benign pituitary adenoma. Materials and methods: The present prospective comparative was conducted in the Department of General Surgery, Pt. J.N.M. Medical College Raipur, C.G., India among 50 patients diagnosed of noninvasive pituitary Adenoma. Group I (n=28); underwent endoscopic transsphenoidal surgery. Group II (n=22): underwent microscopic transsphenoidal surgery. Results: A total of 50 patients with pituitary noninvasive adenoma were operated transsphenoidally. Endonasal endoscopic transsphenoidal surgery (group I) was carried out among 28 patients and 22 patients were operated by microscopic transsphenoidal surgery (group II). In group I, complete tumor excision was achieved in 16 (57.1%) patients, and in group II, it was achieved in 12 (54.5%) patients. Conclusion: Pituitary noninvasive adenomas can be treated with any approach. In compared to microscopic method, endoscopy is superior for resection and has less post-operative complications.

It is very challenging to characterize surface/sub-surface defects for large-aperture optics. The first challenge is the conflict between high resolution and large field of view, namely how to reach a good balance between high resolution and high efficiency for detecting various defects with sub-micronover the meter-size surface of optics. The second challenge is how to classify defects accurately, which is very important for determining origin of defects and improving optics quality.In this paper, a multimodal inspection technique for surface/sub-surface defects of large-aperture optics is reported, in which a high speed laser scattering imaging with a sensitivity at 200-nm scale is used for defect discovery of large-aperture optics. The defect discovery provides a statistical result of defects of the optics. After that, a multifunctional microscopic method is used for local defect review. A photo thermal scanning microscopy is used for specific characterization of absorption defects, and a confocal microscopy is used for characterization of sub-surface defects. The defect review provides information for defect classification. Based on this multimodal technique, an inspection system is also developed and used for defect characterization of large optics.

The object of research is the drying process of the pomace of a walnut kernel, peanuts and pistachios in a fluidized bed dryer with an inert support. One of the most problematic places is the issue of recycling of secondary raw materials, which represent significant potential for the food industry. The solution to the problem that is urgent is the preservation of pomace of the walnut kernel, peanuts and pistachios for their further use in the food industry. At the same time, the advantages of dried semi-finished products: –ability to transport over long distances; –long shelf life of dried products; –use in food technology; –use as a protein supplement. Therefore, the work is devoted to the development of new and modernization of existing drying methods. One of such methods is drying in a fluidized bed of an inert support; this product has not been used before for drying because of the complexity of the process. During the study, the method of microscopic determination of the dispersed composition of the product is used, which allows measuring particles with a size of 0.3-100 microns. Test powders of different fineness are investigated using USB Digital Microscope. The mathematical processing of the results using modern computer programs is carried out. The data obtained are processed in the Mathcad environment and presented as integral and differential particle distribution functions for each analyzed sample. This is due to the fact that the analysis of the determination of the dispersed composition is a mandatory control method in all technological processes. Thanks to this, it is possible to obtain a given product size. In the course of the study, a design of a continuous industrial drying unit for drying pomace of walnut kernels, peanuts and pistachios was developed. The drying method proposed in this work has several advantages over other methods, the main of which are the reduction of energy consumption and improving the quality of the finished product.

The present study investigates the effects of impeller design and dispersed phase volume ratio on mean drop sizes (d32) in immiscible liquid-liquid stirred vessel through experimental and modeling approaches. Various impeller designs including conventional and new impeller designs were employed to cover both radial and axial flow impellers. The microscopic method associated with image processing tools was used for the drop size analysis. The results showed the hydrofoil impeller produced the largest drop sizes while the double-curved blade turbine produced the smallest drop sizes, corresponding to about 37% difference. Increasing the dispersed phase volume ratio from 1% to 10%) increased the d32 by approximately 20–40%. Adaptive neuro-fuzzy inference system based on fuzzy C–means (ANFIS-FCM) clustering algorithm was used to develop a model to predict drop sizes, and its validation and accuracy were examined by comparing the results to the experimental data. The results also proved the superior prediction capability of the ANFIS-FCM method over the empirical correlations for the most cases.

Changes in metallic and nonmetallic materials under the influence of a pulsed magnetic field are studied, using the method of target metallography. It is shown that the structural changes are at the minimum detectable level of the microscopic method with peak gains. It is established that local variation in structure and degradation in the sharpness of separate surface areas of the samples independent of errors in focusing is a general structure change in the action of a magnetic field. The stresses of the third kind are considered to be possible reasons for the change in structure.

Understanding drivers of fish maturity are essential to predict the productivity, stability, and resiliency of exploited populations. In terms of horse mackerel (Trachurus trachurus), in the eastern Atlantic Ocean and the Mediterranean Sea, size at maturity estimates date back to the 1940s and throughout its range. However, many older estimates may not reflect current maturity rates. This is because past methods were imprecise, or environmental or fishing effects may change maturity rates, and some stock areas have been overlooked. To address this data gap for the Central Mediterranean Sea, female horse mackerel size at maturity was estimated for two areas: the Strait of Sicily and the Tyrrhenian Sea. All ovaries were assigned a reproductive phase based on macroscopic methods, and the reliability of this method (94%) was validated with a microscopic method (i.e., gonad histology). Although the collected females exhibited similar condition, in terms of total body weight at a given length, as well as similar gonad-somatic indices, the size at median maturity in the Strait of Sicily was smaller (161 mm total length [TL]) than in the Tyrrhenian Sea (176 mm TL). Future sampling in a series of years with contrasting levels of productivity may help identify whether this is a broad latitudinal trend, or due to specific oceanographic drivers, such as estuarine outflow into the Tyrrhenian Sea or upwelling in the Strait of Sicily. Meanwhile, resource assessments should consider that these two areas represent two phenotypic stocks.

Determination of the stage of sexual maturation of an individual fish is commonly assessed using either microscopic or macroscopic staging. Microscopic staging examines either the internal cellular structure (histology) or the external appearance of the whole-oocyte (whole mount). Macroscopic staging is the visual evaluation of the external gonad development according to a standardised reference scale. Histology is the most widely used microscopic method and highly accurate but expensive and time consuming because it requires specialised equipment. Macroscopic staging is cheaper and faster but is associated with higher degree of error and bias. This study describe a methodological approach to assessing maturity stages of individual fish that is both inexpensive, rapid and more accurate than macroscopic staging. We have named it the gonometric method because it is based on direct measurements of the gonodasomatic index (GSI), which expresses gonad weight as a proportion of total or somatic weight. Immature, mature-active, and mature-inactive fish were classified using a logistic multinomial model giving a threshold value of GSI named here as GSIcut-off. The gonometric method was applied to four fish species that had different reproductive strategies, including demersal and pelagic species. For all four species the gonometric method estimated the maturity ogives with comparable precision to microscopic methods (p > 0.05). Across species, GSIcut-off values correlate with growth parameter of the von Bertalanffy growth function and length at 50% maturity, suggesting that the scaling of the GSIcut-off value is underpinned by fundamental allometric principles. Further testing of the gonometric method is required, but our results suggest that it has considerable potential for providing a faster and more accurate alternative to maturity staging without the need for extensive training requirements to ensure consistency across individual observers.