Optimum sample size to estimate mean parasite abundance in fish parasite surveys
To reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined preci...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Sciendo
2018-03-01
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| Series: | Helminthologia |
| Subjects: | |
| Online Access: | https://doi.org/10.1515/helm-2017-0054 |
| _version_ | 1797720696607997952 |
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| author | Shvydka S. Sarabeev V. Estruch V. D. Cadarso-Suárez C. |
| author_facet | Shvydka S. Sarabeev V. Estruch V. D. Cadarso-Suárez C. |
| author_sort | Shvydka S. |
| collection | DOAJ |
| description | To reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined precision level and parameter of the negative binomial distribution estimated from the empirical data. A simulation approach to optimum sample size determination aimed at the estimation of true value of the mean abundance and its confidence interval (CI) was based on the Bag of Little Bootstraps (BLB). The abundance of two species of monogenean parasites Ligophorus cephali and L. mediterraneus from Mugil cephalus across the Azov-Black Seas localities were subjected to the analysis. The dispersion pattern of both helminth species could be characterized as a highly aggregated distribution with the variance being substantially larger than the mean abundance. The holistic approach applied here offers a wide range of appropriate methods in searching for the optimum sample size and the understanding about the expected precision level of the mean. Given the superior performance of the BLB relative to formulae with its few assumptions, the bootstrap procedure is the preferred method. Two important assessments were performed in the present study: i) based on CIs width a reasonable precision level for the mean abundance in parasitological surveys of Ligophorus spp. could be chosen between 0.8 and 0.5 with 1.6 and 1x mean of the CIs width, and ii) the sample size equal 80 or more host individuals allows accurate and precise estimation of mean abundance. Meanwhile for the host sample size in range between 25 and 40 individuals, the median estimates showed minimal bias but the sampling distribution skewed to the low values; a sample size of 10 host individuals yielded to unreliable estimates. |
| first_indexed | 2024-03-12T09:23:13Z |
| format | Article |
| id | doaj.art-62c76ad2479042ed833eff970d788f0d |
| institution | Directory Open Access Journal |
| issn | 0440-6605 1336-9083 |
| language | English |
| last_indexed | 2024-03-12T09:23:13Z |
| publishDate | 2018-03-01 |
| publisher | Sciendo |
| record_format | Article |
| series | Helminthologia |
| spelling | doaj.art-62c76ad2479042ed833eff970d788f0d2023-09-02T14:23:20ZengSciendoHelminthologia0440-66051336-90832018-03-01551525910.1515/helm-2017-0054helm-2017-0054Optimum sample size to estimate mean parasite abundance in fish parasite surveysShvydka S.0Sarabeev V.1Estruch V. D.2Cadarso-Suárez C.3Department of Mathematics, Zaporizhzhia National University, Zhukovskogo 66, 69063Zaporizhzhia, UkraineDepartment of Biology, Zaporizhzhia National University, Zhukovskogo 66, 69063Zaporizhzhia, Ukraine; volodimir.sarabeev@gmail.comResearch Institute for Integrated Management of Coastal Zones, Department of Applied Mathematics, Polytechnic University of Valencia, Paranimf, 1, 46730 Grau de Gandia, SpainUnit of Biostatistics, Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela, Av. Barcelona, 15782Santiago de Compostela, SpainTo reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined precision level and parameter of the negative binomial distribution estimated from the empirical data. A simulation approach to optimum sample size determination aimed at the estimation of true value of the mean abundance and its confidence interval (CI) was based on the Bag of Little Bootstraps (BLB). The abundance of two species of monogenean parasites Ligophorus cephali and L. mediterraneus from Mugil cephalus across the Azov-Black Seas localities were subjected to the analysis. The dispersion pattern of both helminth species could be characterized as a highly aggregated distribution with the variance being substantially larger than the mean abundance. The holistic approach applied here offers a wide range of appropriate methods in searching for the optimum sample size and the understanding about the expected precision level of the mean. Given the superior performance of the BLB relative to formulae with its few assumptions, the bootstrap procedure is the preferred method. Two important assessments were performed in the present study: i) based on CIs width a reasonable precision level for the mean abundance in parasitological surveys of Ligophorus spp. could be chosen between 0.8 and 0.5 with 1.6 and 1x mean of the CIs width, and ii) the sample size equal 80 or more host individuals allows accurate and precise estimation of mean abundance. Meanwhile for the host sample size in range between 25 and 40 individuals, the median estimates showed minimal bias but the sampling distribution skewed to the low values; a sample size of 10 host individuals yielded to unreliable estimates.https://doi.org/10.1515/helm-2017-0054fishligophorus spp.mean abundanceoptimum sample sizeprecisionbag of little bootstraps |
| spellingShingle | Shvydka S. Sarabeev V. Estruch V. D. Cadarso-Suárez C. Optimum sample size to estimate mean parasite abundance in fish parasite surveys Helminthologia fish ligophorus spp. mean abundance optimum sample size precision bag of little bootstraps |
| title | Optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| title_full | Optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| title_fullStr | Optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| title_full_unstemmed | Optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| title_short | Optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| title_sort | optimum sample size to estimate mean parasite abundance in fish parasite surveys |
| topic | fish ligophorus spp. mean abundance optimum sample size precision bag of little bootstraps |
| url | https://doi.org/10.1515/helm-2017-0054 |
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