ORCID Profile
0000-0002-9809-9672
Current Organisations
Brien Holden Vision Institute
,
University of New South Wales School of Optometry and Vision Science
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Informa UK Limited
Date: 09-2014
DOI: 10.1111/CXO.12173
Abstract: Selection of a standard professional is crucial for assessing the clinical performance of other eye-care personnel. This paper describes the selection considerations and the clinical competency assessment of two optometrists required to select a 'standard optometrist' (SO) for evaluating the clinical performance of vision technicians in India. Two optometrists were short-listed from 21 optometrists who responded to an advertisement to be selected as a SO for the assessment of the performance of 24 vision technicians in rural vision centres. Each candidate optometrist performed a routine eye examination on 40 randomly selected, newly registered subjects in a tertiary hospital clinic. Their non-cycloplegic retinoscopic findings were compared with those of an experienced optometrist, while disease diagnoses were compared with the findings of an ophthalmologist. A comparison of retinoscopic findings showed that optometrist A produced retinoscopic values within ±0.50 D agreement for the spherical equivalent (SE) 100 per cent of the time, while optometrist B obtained agreement 91.3 per cent of the time. Similarly, optometrist A's limits of agreement (SE = -0.63 to +0.45 D) and reproducibility limits (SE = 0.78 D) were better than those of optometrist B (SE = -0.98 to +0.70 D and SE =1.18 D, respectively). Optometrist A demonstrated 89.2 per cent sensitivity in detecting ocular pathology compared to 76.3 per cent by optometrist B. Optometrist A achieved consistent and reproducible retinoscopic findings as well as higher sensitivity in detecting ocular pathology and was selected as the SO for a study to assess the clinical performance of one-year trained vision technicians. The concept of a SO calibrated against an ophthalmologist for disease detection and diagnosis and an experienced optometrist for retinoscopy is a useful approach for the evaluation of eye-care personnel.
Publisher: Informa UK Limited
Date: 09-2020
DOI: 10.1111/CXO.13042
Publisher: Wiley
Date: 28-01-2014
DOI: 10.1111/CEO.12273
Publisher: Informa UK Limited
Date: 02-11-2015
DOI: 10.3109/09286586.2015.1057604
Abstract: To determine how people attending outreach eye care clinics in Papua New Guinea (PNG) perceive eye health and eye health services. An interview-based questionnaire was administrated to a convenience s le of 614 adult participants across four provinces and perceptions of eye health and eye health services were recorded. Presenting and near visual acuity were measured and cause of visual impairment (VI) determined. In this s le, 113/614 participants (18.4%) presented with distance VI, 16 (2.6%) with distance blindness, and 221 (47.6%) with near VI. Older participants and those with near VI were more likely to indicate that it is hard to have an eye examination due to travel time, lack of transport and transport costs. Female participants and those from underserved areas were more likely to report shame and fear of jealousy from others when asked about their attitudes towards spectacles. Participants reporting that they were willing to pay higher amounts for testing and spectacles/treatment also reported higher education levels, higher household incomes and were more likely to be male. A quarter of participants (25.9%) indicated that they did not like having an eye examination because their reading and writing was poor. People attending outreach eye care clinics in PNG reported finding it difficult to attend eye health services due to transport difficulties and anticipated high costs. Negative attitudes towards spectacles were also prevalent, and negative perceptions appeared more frequently among older participants and those with less education.
Publisher: Informa UK Limited
Date: 17-04-2014
DOI: 10.3109/09286586.2014.903980
Abstract: To assess the reasons for refusing cataract surgery in illiterate in iduals in a tribal area of India. A prospective study evaluated 1046 subjects who had undergone screening in eye c s and included 398 of 492 referred subjects with cataract who refused to seek cataract surgery. Subjects were assessed to elicit general and specific reasons for non-compliance. Multiple logistic regression analysis was applied to determine the associations p < 0.05 was considered significant. Overall, 83% (329/398) of subjects reported that they could manage with their current vision. The five most common reasons they did not proceed with cataract surgery were: fear of losing current vision, work priority, lack of support systems, a dependency due to old age, and expenses required after surgery. Odds of seeking treatment were lower among unemployed subjects (odds ratio, OR, 0.4, 95% confidence interval, CI, 0.19-0.86 p = 0.01) and in patients with family income <1000 Indian rupees per month (OR 0.5, 95% CI 0.34-0.94 p = 0.02), and higher among those unilaterally blind (OR 10.8, 95% CI 3.3-35.6 p ≤ 0.01). In a tribal setting, 83% of in iduals referred for cataract surgery did not proceed with surgery. Reasons given for non-compliance were not directly related to the surgery but focused on valid day-to-day difficulties anticipated to increase following surgery. Beyond accessibility and cost of surgery, other social and infrastructural factors need to be addressed to increase the uptake of cataract surgery.
Publisher: Informa UK Limited
Date: 10-01-2023
Publisher: Medknow
Date: 2012
Publisher: Oxford University Press (OUP)
Date: 06-10-2019
Abstract: Health promotion intervention in schools is a useful strategy to improve students' health awareness. The purpose of this study was to assess the effect of eye health promotion interventions on eye health literacy in school children in Vietnam. A piloted questionnaire was administered to 300 children from five secondary schools in Ba Ria-Vung Tau, Vietnam at baseline and re-administered after the eye health promotion interventions. McNemar chi-square and logistic regression were used for statistical analysis. A total of 300 children aged 12-15 years (mean, 13.3 ± 1.3 years 60% female) participated in the baseline survey. The participation rate in the post-health promotion survey was 94.7%. After the health promotion interventions, number of children who had correct eye health knowledge increased by 10-20% (60-75% to 70-95%), more children reported having had an eye examination (63.3% to 84.7% p < 0.001) and more reported wearing spectacles (36.1% to 43.4% p = 0.04). Children in urban schools were twice as likely to have improved knowledge of vision loss compared with children in rural schools (odds ratio, 2.1-4.1 p = 0.01 to p < 0.001). Children from rural schools had significantly higher odds of visiting doctor after the eye problems worsened (odds ratio, 4.5 p < 0.001). These results imply that eye health promotion interventions significantly improve eye health knowledge, attitudes and practices of school children. Additionally, participation of parents and teachers as change agents may further improve children's health literacy.
Publisher: Springer Singapore
Date: 2021
Publisher: Journal of Nepal Medical Association (JNMA)
Date: 28-02-2019
DOI: 10.31729/JNMA.3523
Abstract: Optometry is an independent profession which is specialised for providing comprehensive eye care including refraction and dispensing services, diagnosis and management of eye diseases and visual rehabilitation. In clinical settings of Nepal, optometrists are primarily recognised as refractionists and are provided with working opportunities in the same area. This report highlights other optomet- ric services such as binocular vision, multifocal lenses, contact lenses and occupational lens design which can be provided by optometrists besides performing refraction and prescribing spectacles. Considering large proportion of optometrists with further education and being working outside the country, new specialised services can be introduced through training and workshop to the fellow optometrists so that specialised services can reach up to the public level. Keywords: Nepal optometry refraction services.
Publisher: Wiley
Date: 02-10-2014
DOI: 10.1111/CEO.12413
Abstract: The aim of this study was to develop and validate a new vision-specific quality of life (VS QoL) instrument and to assess the impact of vision impairment and eye disease on the quality of life of adults in Papua New Guinea (PNG). This study was designed as community based cross-sectional. Six hundred fourteen adults aged 18 and above were included in this study. Focus groups and interviews guided development of a 41-item instrument. Two valid subscales of the instrument were obtained using pilot data after an iterative item reduction process guided by Rasch-based parameters. The person measures (in logits) of 614 participants were used to assess quality of life using univariate and multivariate regression analysis. Rasch logits. Rasch analysis confirmed a 17-item instrument containing an 8-item activity limitation subscale and a 9-item well-being subscale. Both subscales were unidimensional and demonstrated good fit statistics, measurement precisions and absence of significant differential item functioning. A consistent deterioration in vision-specific quality of life was independently and significantly associated with levels of vision. Severity of vision impairment and ocular morbidity were independently associated with activity limitation and emotional well-being. Participants with refractive error had lower quality of life score than those with no ocular abnormality but higher score than those with cataract and other eye diseases. The 17-item PNG-VS QoL instrument is a valid and reliable instrument for the assessment of impact of impaired vision on quality of life in PNG. Vision-specific quality of life was significantly worse among participants who were older and less-educated, had lower income and have had ocular morbidities.
Publisher: Informa UK Limited
Date: 10-05-2021
Publisher: BMJ
Date: 02-2021
DOI: 10.1136/BMJOPHTH-2020-000654
Abstract: To determine willingness to pay for children’s spectacles, and barriers to purchasing children’s spectacles in Cambodia. We conducted vision screenings, and eye examinations as indicated, for all consenting children at 21 randomly selected secondary schools. We invited parents/guardians of children found to have refractive problems to complete a willingness to pay for spectacles survey, using a binary-with-follow-up technique. We conducted vision screenings on 12 128 secondary schoolchildren, and willingness to pay for spectacles surveys with 491 parents/guardians (n=491) from Kandal and Phnom Penh provinces in Cambodia. We found 519 children with refractive error, 7 who had pre-existing spectacles and 14 recommended spectacles for lower ametropias. About half (53.2% 95% CI 44.0% to 62.1%) of parents/guardians were willing to pay KHR70 000 (US$17.5 average market price) or more for spectacles. Mean willingness-to-pay price was KHR74 595 (US$18.6 95% CI KHR64 505 to 86 262 95% CI US$16.1 to US$21.6) in Phnom Penh and KHR55 651 (US$13.9 95% CI KHR48 021 to 64 494 95% CI US$12.0 to US$16.1) in Kandal province. Logistic regression suggested parents/guardians with college education (OR 6.8 p .001), higher household incomes (OR 8.0 p=0.006) and those wearing spectacles (OR 2.2 p=0.01) were more likely to be willing to pay ≥US$17.5. The most common reasons for being unwilling to pay US$17.5 were related to cost (58.8%). The most common barrier to spectacle wear was fear that spectacles weaken children’s eyes (36.0%). With almost half of parents/guardians unwilling to pay for spectacles at the current average market price, financial support through a subsidised spectacle scheme might be required for children to access spectacles in Cambodia.
Publisher: Wiley
Date: 07-02-2023
DOI: 10.1111/OPO.13105
Abstract: S ling and describing the distribution of refractive error in populations is critical to understanding eye care needs, refractive differences between groups and factors affecting refractive development. We investigated the ability of mixture models to describe refractive error distributions. We used key informants to identify raw refractive error datasets and a systematic search strategy to identify published binned datasets of community‐representative refractive error. Mixture models combine various component distributions via weighting to describe an observed distribution. We modelled raw refractive error data with a single‐Gaussian (normal) distribution, mixtures of two to six Gaussian distributions and an additive model of an exponential and Gaussian (ex‐Gaussian) distribution. We tested the relative fitting accuracy of each method via Bayesian Information Criterion (BIC) and then compared the ability of selected models to predict the observed prevalence of refractive error across a range of cut‐points for both the raw and binned refractive data. We obtained large raw refractive error datasets from the United States and Korea. The ability of our models to fit the data improved significantly from a single‐Gaussian to a two‐Gaussian‐component additive model and then remained stable with ≥3‐Gaussian‐component mixture models. Means and standard deviations for BIC relative to 1 for the single‐Gaussian model, where lower is better, were 0.89 ± 0.05, 0.88 ± 0.06, 0.89 ± 0.06, 0.89 ± 0.06 and 0.90 ± 0.06 for two‐, three‐, four‐, five‐ and six‐Gaussian‐component models, respectively, tested across US and Korean raw data grouped by age decade. Means and standard deviations for the difference between observed and model‐based estimates of refractive error prevalence across a range of cut‐points for the raw data were −3.0% ± 6.3, 0.5% ± 1.9, 0.6% ± 1.5 and −1.8% ± 4.0 for one‐, two‐ and three‐Gaussian‐component and ex‐Gaussian models, respectively. Mixture models appear able to describe the population distribution of refractive error accurately, offering significant advantages over commonly quoted simple summary statistics such as mean, standard deviation and prevalence.
Publisher: Oxford University Press (OUP)
Date: 12-07-2017
DOI: 10.1093/JTM/TAX044
Abstract: Travellers are at risk of acquiring infectious diseases during travel, with risks differing by destination, travel and traveller characteristics. A pre-travel health consultation may minimize this risk. However, uptake of pre-travel health advice remains low. We investigated pre-travel health preparations and disease-specific risk behaviours among notified cases of selected travel-associated infectious diseases imported into Australia. Prospective enhanced surveillance of notified cases of typhoid, paratyphoid, measles, hepatitis A, hepatitis E, malaria and chikungunya was conducted in two Australian states between February 2013 and January 2014. Details of pre-travel health preparation and disease-specific risk behaviours were collected. Among 180 cases associated with international travel, 28% were <18 years, 65% were VFR travellers and 22% were frequent travellers, having travelled ≥5 times in the past 5 years. 25% had sought pre-travel advice from a healthcare provider, and 16% reported a pre-travel vaccine. Seeking pre-travel health advice did not differ by immigrant status ( P = 0.22) or by reason for travel ( P = 0.13) but was more commonly sought by first time travellers ( P = 0.03). Travellers visiting friends and relatives were more likely to report at-risk activities of brushing teeth with tap water ( P < 0.001) and eating uncooked food ( P = 0.03) during travel compared to other travellers. Pre-travel health advice seeking practices and vaccine uptake was suboptimal among cases of notified disease. The results of this study highlight the need for a better understanding of barriers to pre-travel health seeking, particularly among high risk travellers, to reduce the importation of infectious diseases into Australia.
Publisher: Informa UK Limited
Date: 02-11-2015
DOI: 10.3109/09286586.2015.1082605
Abstract: To assess clinical competency of 1-year trained vision technicians (VTs) in detecting and referring causes of visual impairment in India. Eye examination results and management plans for 328 patients examined by 24 VTs in 24 vision centers of LV Prasad Eye Institute in Andhra Pradesh were compared with those of a standard optometrist who examined the same patients. Eye examinations included retinoscopy and subjective refraction, slit l examination, applanation tonometry and undilated direct ophthalmoscopy. Data were analyzed for level of concordance in retinoscopy, spectacle prescription, disease detection and referral. VTs demonstrated moderate to good levels of agreement in refraction, disease detection and referral. Sensitivity and specificity for ocular pathology identification were 77.4% (95% confidence interval, CI, 69.4-84.2%) and 86.6% (95% CI 81.1-91.1%), respectively. The highest sensitivity was demonstrated in detecting significant cataract (91.5%) and refractive error (83.0%). VT spectacle prescriptions were accurate 76% of the time for mean spherical equivalent and 65% of the time for astigmatism. VT sensitivity in detecting posterior segment abnormalities was low (18.5%) resulting in failure to detect retinal conditions such as diabetic retinopathy and maculopathy. Despite lack of recognition of the specific pathology, referral decisions were correct in 78.4% of cases. VTs in India competently detect and manage or refer the two most common causes of visual impairment uncorrected refractive error and cataract. Over two-thirds of patients received accurate and appropriate services from VTs, suggesting that they are a useful and competent cadre for rural and remote eye care.
Publisher: Informa UK Limited
Date: 02-01-2016
DOI: 10.3109/09286586.2015.1082602
Abstract: To assess validity of teacher-based vision screening and elicit factors associated with accuracy of vision screening in Vietnam. After brief training, teachers independently measured visual acuity (VA) in 555 children aged 12-15 years in Ba Ria - Vung Tau Province. Teacher VA measurements were compared to those of refractionists. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for uncorrected VA (UVA) and presenting VA (PVA) 20/40 or worse in either eye. Chi-square, Fisher's exact test and multivariate logistic regression were used to assess factors associated with accuracy of vision screening. Level of significance was set at 5%. Trained teachers in Vietnam demonstrated 86.7% sensitivity, 95.7% specificity, 86.7% positive predictive value and 95.7% negative predictive value in identifying children with visual impairment using the UVA measurement. PVA measurement revealed low accuracy for teachers, which was significantly associated with child's age, sex, spectacle wear and myopic status, but UVA measurement showed no such associations. Better accuracy was achieved in measurement of VA and identification of children with visual impairment using UVA measurement compared to PVA. UVA measurement is recommended for teacher-based vision screening programs.
Publisher: Informa UK Limited
Date: 2016
DOI: 10.1111/CXO.12446
Abstract: The aim of this study was to investigate the current situation of low vision services and barriers to low vision service delivery in Papua New Guinea (PNG). An exploratory study was undertaken to assess the situation of available services, human resources, training, equipment and assistive devices, supportive policies, needs of people with low vision and community attitudes toward people with low vision. In-depth interviews with 50 key informants were conducted in-country. Key informants included eye-care practitioners (n = 13), special education teachers (n = 10), community-based rehabilitation workers (n = 3), other stakeholders providing disability-related services (n = 8), and people with low vision (n = 14) and their family members (n = 2). Interview transcripts were analysed inductively and deductively using thematic analysis. Barriers were identified at systems and community levels. The barriers at the systems level were: low vision not a priority area for eye care and rehabilitation programs, limited availability of low vision services, trained personnel and low vision devices low vision not included in training programs of eye-care practitioners and lack of awareness of available referral services among service providers. The barriers identified at the community level were lack of awareness of services, distance, costs and limited transport to access services and negative community attitudes. This study has identified barriers from the perspectives of different stakeholders, including service providers and people with low vision and their families. Knowledge of these barriers can now guide the development of future low vision services in PNG.
Publisher: Elsevier BV
Date: 04-2017
Publisher: Elsevier BV
Date: 09-2005
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.CLAE.2013.07.001
Abstract: To determine the rates of microbial contamination and identify contaminants associated with contact lens (CL) care accessories. To investigate self-reported compliance levels with care of CL accessories and its association with contamination level. A total of 46 CL cases and care solutions from asymptomatic soft contact lens wearers were collected. S les from the CL cases and care solutions were cultured for microbiological identification and enumeration. A questionnaire regarding compliance to care and hygiene procedures were administered to each subject on their visit. The percentage of microbial contamination for CL cases and care solutions was 50% and 10.9%, respectively. All the contaminants were bacterial. Staphylococcus aureus (37.0%, 17 of 46 cases) and Escherichia coli (8.7%, 4 of 46 cases) were the most common microorganisms detected in CL cases. In care solutions, S. aureus (8.7%, 4 of 46 s les), Pseudomonas aeruginosa (2.2%, 1 of 46 s les) were common contaminants. CL cases and care solutions that were used for 3 months (10.9% versus 39.1%, p<0.05). Polyquad and Aldox based MPS solution showed no contamination. Subjects with medium or low compliance had highly significant rates of contaminations both in CL cases and solutions than for subjects with high compliance (p<0.05). Nepalese Soft CL wearers are at high risk of developing ocular complications due to high CL case and solution contamination. Frequent replacement of CL cases and solutions, as well as good compliance is recommended to reduce risk of contamination.
Publisher: AOSIS
Date: 30-10-2019
Location: Australia
No related grants have been discovered for Prakash Paudel.