The influence of corneal density and thickness on tonometry measurement with goldmann applanation, non-contact and iCare tonometry methods

Abstract Purpose To evaluate the effect of corneal density and thickness on the accuracy of tonometry readings obtained via three most used techniques. Method Intraocular pressures of 45 patients’ right eyes were measured using Goldmann Applanation, iCare, and non-contact tonometry methods. Corneal parameters were obtained using the Pentacam Camera System. Data obtained were analyzed using Paired t Test, Pearson’s correlation coefficient, multiple linear regression analysis, and Bland–Altman plots. Results The mean corneal thickness was 545.4 ± 3.93 μm. The mean corneal density of total, stromal, 0–2 mm, and 2–6 mm zones were 27.85 ± 6.23 GSU, 24.61 ± 6.05 GSU, 20.76 ± 2.96 GSU, and 20.81 ± 3.51 GSU respectively. IOP readings had a statistically significant correlation with corneal stromal thickness, as well as with total and stromal density. The stromal density, however, showed higher correlation with the three tonometry methods than did the total density (iCare: − .482 (0.001) stromal density versus− .464 (0.001) total density, NCT: − .376 (0.011) versus − .353 (0.017), GAT: − .306 (0.041) versus − .296 (0.048)). Statistical differences were found in comparing the iCare readings with GAT (P < 0,00) and with NCT (P < 0,00), with mean differences of 1.8 mmHg ± 2.6 and 2.0 mmHg ± 2.6 respectively. GAT and NCT measurements showed no statistical difference (P > 0.05). Conclusion This study shows that both central corneal thickness and stromal density are significant influential factors of reliable IOP readings. It is necessary to consider more corneal biomechanical properties, as well as exercise a high degree of caution in any new attempts towards adjusting an IOP-correction equation.

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Corneal Parameters in Healthy Subjects Assessed by Corvis ST

Journal of Ophthalmic and Vision Research ◽

10.18502/jovr.v15i1.5936 ◽

2020 ◽

Author(s):

Ramin Salouti ◽

Mansoureh Bagheri ◽

Anis Shamsi ◽

Mohammad Zamani ◽

Maryam Ghoreyshi ◽

...

Keyword(s):

Linear Regression Analysis ◽

Corneal Thickness ◽

Case Series ◽

Biomechanical Properties ◽

Radius Of Curvature ◽

Corvis St ◽

Deformation Amplitude ◽

Study Results ◽

The Mean ◽

The Right

Purpose: To evaluate corneal biomechanics using Corvis ST in healthy eyes from Iranian keratorefractive surgery candidates. Methods: In this prospective consecutive observational case series, the intraocular pressure (IOP), central corneal thickness (CCT), and biomechanical properties of 1,304 eyes from 652 patients were evaluated using Corvis ST. Keratometric readings and manifest refraction were also recorded. Results: The mean (±SD) age of participants was 28 ± 5 years, and 31.7% were male. The mean spherical equivalent refraction was –3.50 ± 1.57 diopters (D), the mean IOP was 16.8 ± 2.9 mmHg, and the mean CCT was 531 ± 31 μm for the right eye. The respective means (±SD) corneal biomechanical parameters of the right eye were as follows: first applanation time: 7.36 ± 0.39 milliseconds (ms); first applanation length: 1.82 ± 0.22 mm; velocity in: 0.12 ± 0.04 m/s; second applanation time: 20.13 ± 0.48 ms; second applanation length: 1.34 ± 0.55 mm; velocity out: –0.67 ± 0.17 m/s; total time: 16.84 ± 0.64 ms; deformation amplitude: 1.05 ± 0.10 mm; peak distance: 4.60 ± 1.01 mm; and concave radius of curvature: 7.35 ± 1.39 mm. In the linear regression analysis, IOP exhibited a statistically significant association with the first and second applanation times, total time, velocity in, peak distance, deformation amplitude, and concave radius of curvature. Conclusion: Our study results can be used as a reference for the interpretation of Corvis ST parameters in healthy refractive surgery candidates in the Iranian population. Our results confirmed that IOP is a major determinant of Corvis parameters.

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Changes in corneal properties and its effect on intraocular pressure measurement following phacoemulsification with intraocular lens implantation with or without trabeculectomy

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v16i1.344 ◽

2018 ◽

Vol 16 (1) ◽

pp. 35-50

Author(s):

Ashim Dey ◽

RathiniLilian David ◽

Rashima Asokan ◽

Ronnie George

Keyword(s):

Intraocular Lens ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Normal Subjects ◽

Biomechanical Properties ◽

Multiple Linear Regression Analysis ◽

Iol Implantation ◽

Postoperative Changes ◽

Applanation Tonometer ◽

Iop Measurement

Purpose: To evaluate the changes incorneal biomechanical properties and their effect on pre and postoperative differences in IOP measurement by each tonometer Design: Observational study. Methods: The study was done in subjects who underwent phacoemulsification with intraocular lens (IOL) implantation (phaco-IOL) and combined phacoemulsification with IOL implantation and trabeculectomy (phaco-trab). IOP was measured by a single trained examiner using rebound tonometer (RBT), Ocular Response Analyzer (ORA), Goldmann applanation tonometer (GAT), dynamic contour tonometer (DCT), and Tono-Pen. Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured using ORA, central corneal thickness (CCT) using ultrasonic pachymeter, and corneal curvature (CR) with manual keratometry. All measurements were done one week prior to surgery and after four weeks and six weeks of the two surgeries, respectively. Only the operated eye was included for analysis. Results: Twenty-nine eyes of 29 normal subjects who underwent phaco-IOL and 23 eyes of 23 glaucoma subjects who underwent phaco-trab were studied. Increase in CCT [10.2 ± 14.86 microns, p = 0.001], decrease in CH [0.82 ± 1.38 mmHg, p = 0.003] and CRF [0.97 ± 1.0 mmHg, p < 0.001] were found post-phaco-IOL, whereas post-phaco-trab decrease in CCT [16.61 ± 15.22 microns, p < 0.001], CRF [2.28 ± 1.93 mmHg, p < 0.001] with increase in CH [0.95 ± 1.89 mmHg, p = 0.03] were noted. Multiple linear regression analysis showed significant associations for change in CH and CRF with change in IOP and not with CCT and CR postoperatively. Conclusion: Alterations in CH and CRF were associated with changes in IOP measured postoperatively by different tonometers. CH and CRF changes contribute to postoperative changes in measured IOP.

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ANALISIS PERSEPSI PETANI TERHADAP PROGRAM KAWASAN RUMAH PANGAN LESTARI DI KAMPUNG DOSAI DISTRIK SENTANI BARAT KABUPATEN JAYAPURA PROVINSI PAPUA

SEPA Jurnal Sosial Ekonomi Pertanian dan Agribisnis ◽

10.20961/sepa.v15i2.26092 ◽

2019 ◽

Vol 15 (2) ◽

pp. 128

Author(s):

Edison Ayakeding ◽

Keppi Sukesi ◽

Yayuk Yuliati

Keyword(s):

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Individual Characteristics ◽

Influential Factors ◽

Community Empowerment ◽

Program Testing ◽

Food Research ◽

Food And Nutrition ◽

Observation Method ◽

The Individual

Papua is one of the provinces in Indonesia which has the characteristics of a different man in the business of fulfilling the needs of the family. The program of the Ministry of agriculture through community empowerment efforts to optimize the benefits of the grounds as a source of food family. Jayapura Regency is one of the areas that are also experiencing food security problems. Adequacy of food and nutrition is one of the most influential factors in producing quality human resources. The purpose of this research is to analyze the perceptions and the factors that influence the perception of farmers against the program Area Homes Preserved Food. Research conducted in the Western County of Sentani Dosai district of Jayapura of Papua by engaging 25 respondents who implement programs KRPL in 2013. The technique of collecting data through observation method, Now as well as granting interviews specifically. Type a descriptive quantitative data. The measurement of perception of farmers using likert scale gauge. The results of the measurements indicate that the level of perception of farmers against very low KRPL program. Testing free variables using multiple linear regression analysis. The results of the analysis showed that the fulfillment of the needs and knowledge of the real effect, While the individual characteristics, experience factor farmer KRPL and support agencies have no effect on real. The value of R-sq (adj) indicates the magnitude of the influence of variables against the perception that is free of 46.83%, While the 53.17% influenced by other factors outside of this research.Abstrak: Papua merupakan salah satu provinsi di Indonesia yang memiliki karakteristik manusia yang berbeda-beda dalam usaha pemenuhan kebutuhan keluarga. Program Kementerian Pertanian melalui upaya pemberdayaan masyarakat untuk mengoptimalkan manfaat pekarangan sebagai sumber pangan keluarga. Kabupaten Jayapura merupakan salah satu daerah yang juga mengalami masalah ketahanan pangan. Kecukupan pangan dan gizi merupakan salah satu faktor yang berpengaruh dalam menghasilkan sumber daya manusia yang berkualitas. Tujuan penelitian ini adalah menganalisis persepsi dan faktor-faktor yang mempengaruhi persepsi petani terhadap program Kawasan Rumah Pangan Lestari. Penelitian dilakukan di Kampung Dosai Distrik Sentani Barat Kabupaten Jayapura Papua dengan melibatkan 25 responden yang melaksanakan program KRPL pada tahun 2013. Teknik Pengumpulan data melalui metode observasi, pemberian angket serta wawancara secara spesifik. Jenis data deskriptif kuantitatif. Pengukuran persepsi petani menggunakan alat ukur skala likert. Hasil pengukuran menunjukkan bahwa tingkat persepsi petani terhadap program KRPL sangat rendah. Pengujian variabel bebas menggunakan alat analisis regresi linier berganda. Hasil analisis menunjukkan bahwa faktor pemenuhan kebutuhan dan pengetahuan berpengaruh nyata sedangkan faktor karakteristik individu, pengalaman usaha tani KRPL dan dukungan instansi tidak berpengaruh nyata. Nilai R-sq(adj) menunjukan besarnya pengaruh variabel bebas terhadap persepsi yaitu sebesar 46,83%, sedangakan 53,17% dipengaruhi faktor-faktor lain diluar dari pada penelitian ini.

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Relationship between novel intraocular pressure measurement from Corvis ST and central corneal thickness and corneal hysteresis

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-314370 ◽

2019 ◽

Vol 104 (4) ◽

pp. 563-568 ◽

Cited By ~ 2

Author(s):

Masato Matsuura ◽

Hiroshi Murata ◽

Yuri Fujino ◽

Mieko Yanagisawa ◽

Yoshitaka Nakao ◽

...

Keyword(s):

Intraocular Pressure ◽

Central Corneal Thickness ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Biomechanical Properties ◽

Applanation Tonometry ◽

Corneal Hysteresis ◽

Corneal Resistance Factor ◽

Corvis St ◽

The Relationship

AimsCorvis ST (CST) yields biomechanical corrected IOP (bIOP) which is purported to be less dependent on biomechanical properties. In our accompanied paper, it was suggested that the repeatability of bIOP is high. The purpose of the current study was to assess the relationship between intraocular pressure (IOP) measured with CST and central corneal thickness (CCT) and corneal hysteresis (CH), in comparison with IOP measured with Goldmann applanation tonometry (GAT) and the ocular response analyzer (ORA).MethodsA total of 141 eyes from 141 subjects (35 healthy eyes and 106 glaucomatous eyes) underwent IOP measurements with GAT, CST and ORA. The relationships between IOP measurements (ORA-IOPg, ORA-IOPcc, CST-bIOP and GAT IOP) and biomechanical properties (CCT, CH and corneal resistance factor (CRF)) were analysed using the linear regression analysis.ResultsIOPg, IOPcc and GAT IOP were significantly associated with CCT (p<0.001), whereas bIOP was not significantly associated with CCT (p=0.19). IOPg, bIOP and GAT IOP were significantly associated with CH (IOPg: p<0.001; bIOP: p<0.001; GAT IOP: p=0.0054), whereas IOPcc was not significantly associated with CH (p=0.18). All of IOP records were associated with CRF (p<0.001).ConclusionThe bIOP measurement from CST is independent from CCT, but dependent on CH and CRF.

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Therapeutic Strategy of Percutaneous Transforaminal Endoscopic Decompression for Stenosis Associated With Adult Degenerative Scoliosis

Global Spine Journal ◽

10.1177/2192568220959036 ◽

2020 ◽

pp. 219256822095903

Author(s):

Lin-Yu Jin ◽

Kun Wang ◽

Zhen-Dong Lv ◽

Xin-Jin Su ◽

Hai-Ying Liu ◽

...

Keyword(s):

Regression Analysis ◽

Cobb Angle ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Lumbar Stenosis ◽

Degenerative Scoliosis ◽

Adult Degenerative Scoliosis ◽

Lateral Subluxation ◽

The Mean ◽

Transforaminal Endoscopic Surgery

Study Design: A retrospective study. Objective: To investigate the effects of percutaneous transforaminal endoscopic decompression (PTED) for lumbar stenosis associated with adult degenerative scoliosis and to analyze the correlation between preoperative radiological parameters and postoperative surgical outcomes. Methods: Two years of retrospective data was collected from 46 patients with lumbar stenosis associated with adult degenerative scoliosis who underwent PTED. The visual analog scale (VAS), Oswestry Disability Index, and modified MacNab criteria were used to evaluate the clinical outcomes. Multiple linear regression analysis was used to analyze the correlation between radiological parameters and surgical outcomes. Results: The mean age of the 33 female and 13 male patients was 73.5 ± 8.1 years. The mean follow-up was 27.6 ± 3.5 months (range from 24 to 36). The average coronal Cobb angle was 24.5 ± 8.2°. There were better outcomes of the VAS for leg pain and Oswestry Disability Index after surgery. Based on the MacNab criteria, excellent or good outcomes were noted in 84.78% of patients. Multiple linear regression analysis showed that Cobb angle and lateral olisthy may be the predictors for low back pain. Conclusion: Transforaminal endoscopic surgery may be an effective and safe method for geriatric patients with lumbar stenosis associated with degenerative scoliosis. The predictive factors of clinical outcomes were severe Cobb angle and high degree lateral subluxation. Transforaminal endoscopic surgery may not be recommended for patients with Cobb angle larger than 30° combined with lateral subluxation.

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Structural and Biomechanical Corneal Differences between Type 2 Diabetic and Nondiabetic Patients

Journal of Ophthalmology ◽

10.1155/2019/3764878 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

João N. Beato ◽

João Esteves-Leandro ◽

David Reis ◽

Manuel Falcão ◽

Vítor Rosas ◽

...

Keyword(s):

Linear Regression ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Biomechanical Properties ◽

Cross Sectional Study ◽

Applanation Tonometry ◽

Multivariate Linear Regression ◽

Multivariate Linear Regression Analysis ◽

Cross Sectional

Purpose. To analyze and compare corneal structural and biomechanical properties, characterized by corneal hysteresis (CH) and resistance factor (CRF), between patients with and without type 2 diabetes mellitus (DM), and determine the main ocular variables that influence them. Methods. Sixty diabetic and 48 age- and sex-matched non-DM patients were enrolled in this cross-sectional study. The DM group was analyzed according to DM duration (<or ≥ 10 years), HbA1c levels (<or ≥ 7%), and presence of retinopathy. CH and CRF were evaluated using the Ocular Response Analyzer® (ORA). Central corneal thickness (CCT) was determined by Scheimpflug tomography (Pentacam® HR). Intraocular pressure was obtained with ORA (IOPcc) and Goldmann applanation tonometry (IOP-GAT). Univariate and multivariate linear regression analyses were performed to evaluate the relationship between demographical, clinical, and ocular variables with the biomechanical properties. Results. There were no statistically significant differences in the CH and the CRF between DM and non-DM groups (p=0.637 and p=0.439, respectively). Also, there was no statistical difference between groups for the CCT, IOPcc, or IOP-GAT. Multivariate linear regression analysis showed that CH was positively associated with CCT (p<0.001) and negatively associated with IOPcc (p<0.001), while CRF was positively associated with CCT (p<0.001) and IOPcc (p=0.014). Conclusion. The CCT and IOPcc were found to be the main parameters that affect corneal biomechanical properties both in diabetics and controls. In this study, there was no significant effect of DM type 2 on corneal biomechanics.

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Empathy and Personality Styles in Medical Students

Revista Colombiana de Psicología ◽

10.15446/rcp.v29n2.82988 ◽

2020 ◽

Vol 29 (2) ◽

pp. 73-87

Author(s):

Yolanda Dávila Pontón ◽

Alejandro Reyes Reyes ◽

Aracelis Calzadilla Núñez ◽

Víctor Patricio Díaz Narváez ◽

Robert Utsman ◽

...

Keyword(s):

Medical Students ◽

Educational Level ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Personality Styles ◽

Empathy Scale ◽

Mean Differences ◽

Student’S T ◽

The Relationship ◽

Student’S T Test

This study aimed to establish the relationship between empathy and personality styles in medical students, considering the differences by gender. The participants were 278 students of the medical career of the Universidad del Azuay, Ecuador. They were evaluated using the Jefferson empathy scale and the Millon Index of Personality Styles. Relationships between empathy and personality styles were examined using Pearson's correlation coefficient and hierarchical multiple linear regression analysis, for comparisons by gender and educational levels; with both Student's t test and analysis of variance used respectively. Results indicated that the factor structure of the empathy scale is invariant between men and women, noticing gender differences in care with compassion and total empathy, with women presenting a higher mean. Differences are observed by educational level, where the general empathy in the first three years grows progressively, and then slightly decrease. In conclusion, female students present a mean score of total empathy greater than men, with differences of empathy according to educational level

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Production Analysis of Green Mussel (Perna viridis) in Lampung Province

e-Jurnal Rekayasa dan Teknologi Budidaya Perairan ◽

10.23960/jrtbp.v8i2.p975-984 ◽

2020 ◽

Vol 8 (2) ◽

pp. 975

Author(s):

Sulvina Sulvina ◽

Zainal Abidin ◽

Supono Supono

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Multiple Linear Regression ◽

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Influential Factors ◽

Perna Viridis ◽

Factors Affecting ◽

Cultivation Process ◽

Quantitative Descriptive

This study was conducted to find out factors affecting and level of mussel production, level of efficiency of using the tools and materials in cultivation process and whether the cultivation of mussels in Pasaran. This study was analyzed using Cobb-Douglass. The study were analyzed in quantitative descriptive, multiple linear regression analysis, and analysis of efficiency. The dependent variable (Y) is the result of production of green mussels cultivation and free variables are the number of bamboos (X 1), the amount of strap (X2), grouper (X3) and labor (X4). Mussel fisherman in Pasaran NPM with Px calculated to obtain the level of efficiency of each factors of production in messels cultivation. Studies show that the most influential factors production are variable bamboo, rope and labor. While the results of analysis the level of efficiency of using tools and materials is not efficient. The number of bamboo and labor should be reduced, because it tends to be a waste and not profitable either technically or economically. The value of the return to scale of 1.22 showed cultivation mussels are on increasing return to scale.

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Stigma Among Patients with HIV/AIDS: A Cross Sectional Study in Malaysia

International Journal of Human and Health Sciences (IJHHS) ◽

10.31344/ijhhs.v4i1.116 ◽

2019 ◽

Vol 4 (1) ◽

pp. 26

Author(s):

Azreen Abdullah ◽

Adibah Hanim Ismail ◽

Ching Siew Mooi

Keyword(s):

Linear Regression Analysis ◽

Multiple Linear Regression Analysis ◽

Cross Sectional Study ◽

Hiv Stigma ◽

People Living With Hiv ◽

Sectional Study ◽

Cross Sectional ◽

The Mean ◽

Living With Hiv ◽

Hiv Aids

Introduction:HIV stigma refers to negative beliefs, feelings and attitudes towards people living with HIV (PLWH), groups associated with PLWH and other key populations at higher risk of HIV infection, such as people who inject drugs, sex workers, men who have sex with men and transgender people. Despite the advancement made in the knowledge and treatment of HIV, PLWH continues to be stigmatized.Objective: To determine the level of HIV stigma and its predictors among people living with HIV/AIDS in a tertiary hospital in Malaysia.Methods: A cross sectional study was conducted among HIV/AIDS patients aged 18 and above at infectious disease clinic in Hospital Sungai Buloh, Gombak, Malaysia. HIV stigma was assessed using Berger’s HIV stigma scale, which is available in Bahasa Malaysia and English.A self-administered questionnaire was used to determine their demographic and clinical characteristics. Multiple linear regression analysis was used to identify the predictors.Results: 526 subjects participated in this study. The mean age of the study population was 33.5± 8.4 years. The majority of the participants were male (90.9%) and contracted HIV through sexual activities (87.8%). The mean score of HIV stigma was 104.7 ± 19.5. Based on multiple linear regression analysis, patients who were unemployed (B = -8.00, 95% confidence interval (CI) = -12.12,-3.88, p = < 0.001) and being on antiretroviral treatment (B = 4.95, 95% (CI) = 0.30, 9.60, p = < 0.037) had higher level of HIV stigma.Conclusions: The level of HIV stigma was high (mean score =104.7 ± 19.5). HIV/AIDS patients who are unemployed and on antiretroviral agents were at risks of having higher level of HIV stigma. Future study is needed urgently to implement intervention that can minimize the stigmatization among patients with HIV/AIDS.International Journal of Human and Health Sciences Vol. 04 No. 01 January’20 Page : 26-35

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Insight and Associated Factors among Patients with Schizophrenia in Mental Specialized Hospital, Ethiopia, 2018

Psychiatry Journal ◽

10.1155/2019/2453862 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Mandaras Tariku ◽

Demeke Demilew ◽

Tolesa Fanta ◽

Meskerem Mekonnen ◽

Dessie Abebaw Angaw

Keyword(s):

Associated Factors ◽

Linear Regression Analysis ◽

Prognostic Indicator ◽

Multiple Linear Regression Analysis ◽

Cross Sectional Study ◽

Cross Sectional ◽

Specialized Hospital ◽

First Onset ◽

The Mean ◽

Negative Syndrome

Background. Insight is the degree of the patient’s awareness and understanding of their attributions, feelings, behavior and disturbing symptoms. Majority of the patients with schizophrenia have poor insight and insight is an important prognostic indicator in schizophrenia to enhance treatment compliances and reducing the risks of clinical deterioration. The main objective of this study was to assess insight and its associated factors among patients with schizophrenia at mental specialized hospital in Ethiopia. Methods. Institutional based cross-sectional study was conducted from May to June 2018 Mental Specialized Hospital among 455 patients with schizophrenia. Insight was measured by an abridged version of Scale to assess unawareness of mental disorder. Positive and Negative Syndrome Scale, Calgary depressive scale, Oslo social support scale was used to identify factors associated with insight. Simple and multiple linear regression analysis were used to assess associated factors of insight in the participants. Results. The mean score of insight was 13.66 (95% CI 13.27, 14.04). Age at first onset of illness, duration of treatments, depressive symptoms were inversely associated with mean insight score; whereas unemployed, positive and negative syndrome, previous hospitalization, >=2 episodes were positively associated with mean insight score. Conclusion. Nearly half of the study participants were scored above the mean insight score so, the clinicians and psychotherapists should have to work together to improve insight among patients with schizophrenia.

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