| 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. |