Elham Mohebbi
1 
, Farin Kamangar
2,3 , Afarin Rahimi-Movaghar
4 , Ali Akbar Haghdoost
5 , Arash Etemadi
2,6, Saber Amirzadeh
7, Farid Najafi
8,9, Fariba Shafeie
10, Ali Fakhari
11, Karim Ghaleban
11, Soodabeh Shahid-Sales
12, Zeinab Sadat Hosseini
13, Mohammad Reza Honarvar
14, Fatemeh Majnooni
15, Maryam Hadji
1, Kazem Zendehdel
1,16*1 Cancer Research Center, Cancer Institute of Iran, Tehran University of Medical Sciences, Tehran, Iran
2 Digestive Oncology Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, Tehran, Iran
3 Department of Biology, School of Computer, Mathematical, and Natural Sciences, Morgan State University, Baltimore, MD, USA
4 Iranian National Center for Addiction Studies (INCAS), Tehran University of Medical Sciences, Tehran, Iran
5 Modeling in Health Research Center, InstiMetabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USAtute for Future Studies in Health, Kerman Medical Science University, Kerman, Iran
6 Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
7 Social Determinants of Health Research Centre, Institute for Futures studies in Health, Kerman University of Medical Sciences, Kerman, Iran
8 Research Center for Environmental Determinants of Health, Institute of Health, Kermanshah Medical Sciences University, Kermanshah, Iran
9 Social Development and Health Promotion Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
10 Treatment Affairs Deputy, Department of Substance Abuse Treatment, Kermanshah University of Medical Sciences, Kermanshah, Iran
11 Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
12 Department of Radiation Oncology, Mashhad University of Medical Sciences, Mashhad, Iran
13 Student Research Committee, Islamic Azad University, Mashhad Branch, Mashhad, Iran
14 Management and Social Development Research Center, Golestan University of Medical Sciences, Gorgan, Iran
15 Public Health Deputy, Golestan University of Medical Sciences, Gorgan, Iran
16 Cancer Biology Research Center, Cancer Institute of Iran, Tehran University of Medical Sciences, Tehran, Iran
Abstract
Background: Measuring the amount of opium use is a challenge in epidemiologic studies. Self-report of amount of opium use at each consumption, widely used in the literature, usually fails to provide a good estimate. The purpose of this study is to systematically study the perceived weight units of reported opium use in Iran, and compare them to the standardized units of weight measurement.
Methods: An exploratory descriptive study was conducted in six major cities of Iran. Study participants were interviewed and asked to use a Play-Doh-like material to demonstrate the amount of opium they use. To obtain an estimate of the weight of the material used, we multiplied the volume by the density of the opium product. We experimentally determined the density of the commonly used opium products. We used medians and inter-quartile ranges (IQRs) to report the typical amount of each unit.
Results: A total of 108 individuals participated in this study. The most frequently reported unit was “gram”; the median perceived weight for one gram (g) of opium was 0.24 (IQR: 0.16) g. The second most commonly used unit was nokhod with a median of 0.16 (IQR: 0.16) g, followed by mesghaal and hab/habeh, which were 1.28 (IQR: 0.81) and 0.16 (IQR: 0.16) g, respectively. The median perceived weight of mesghaal and gram in the studied cities was less than the expected standardized values.
Conclusion: In conclusion, the reported amount of opium use is highly inaccurate and unreliable, and is mainly subject to underestimation.