American Journal of Public Health May 1 2007, Volume 97, Issue 5 , pp. 780-957 LETTERS: Gregory Todd Jones AGENT-BASED MODELING: USE WITH NECESSARY CAUTION Am J Public Health 2007 97: 780-781, 10.2105/AJPH.2006.109058. Igor Mezic, Paul J. Gruenewald, Dennis M. Gorman, and Jadranka Mezic MEZIC ET AL. RESPOND Am J Public Health 2007 97: 781-782, 10.2105/AJPH.2007.109710. ERRATUM: ERRATA Am J Public Health 2007 97: 782, 10.2105/AJPH.2005.078121e. EDITOR'S CHOICE: Farzana Kapadia Closing the Gaps Am J Public Health 2007 97: 783, 10.2105/AJPH.2007.112607. PUBLIC HEALTH THEN AND NOW: Naomi Rogers Race and the Politics of Polio: Warm Springs, Tuskegee, and the March of Dimes Am J Public Health 2007 97: 784-795, 10.2105/AJPH.2006.095406. FRAMING HEALTH MATTERS: Jeremy Shiffman Generating Political Priority for Maternal Mortality Reduction in 5 Developing Countries Am J Public Health 2007 97: 796-803, 10.2105/AJPH.2006.095455. RESEARCH AND PRACTICE: Jennifer Prah Ruger and Hak-Ju Kim Out-of-Pocket Healthcare Spending by the Poor and Chronically Ill in the Republic of Korea Am J Public Health 2007 97: 804-811, 10.2105/AJPH.2005.080184. Amanda Sacker, Richard D. Wiggins, Mel Bartley, and Peggy McDonough Self-Rated Health Trajectories in the United States and the United Kingdom: A Comparative Study Am J Public Health 2007 97: 812-818, 10.2105/AJPH.2006.092320. Richard T. Enander, Ronald N. Gagnon, R. Choudary Hanumara, Eugene Park, Thomas Armstrong, and David M. Gute Environmental Health Practice: Statistically Based Performance Measurement Am J Public Health 2007 97: 819-824, 10.2105/AJPH.2006.088021. Maria Argos, Faruque Parvez, Yu Chen, A.Z.M. Iftikhar Hussain, Hassina Momotaj, Geoffrey R. Howe, Joseph H. Graziano, and Habibul Ahsan Socioeconomic Status and Risk for Arsenic-Related Skin Lesions in Bangladesh Am J Public Health 2007 97: 825-831, 10.2105/AJPH.2005.078816. Robin Phinney, Sheldon Danziger, Harold A. Pollack, and Kristin Seefeldt Housing Instability Among Current and Former Welfare Recipients Am J Public Health 2007 97: 832-837, 10.2105/AJPH.2005.082677. Bruno Federico, Giuseppe Costa, and Anton E. Kunst Educational Inequalities in Initiation, Cessation, and Prevalence of Smoking Among 3 Italian Birth Cohorts Am J Public Health 2007 97: 838-845, 10.2105/AJPH.2005.067082. Joseph N.S. Eisenberg, James C. Scott, and Travis Porco Integrating Disease Control Strategies: Balancing Water Sanitation and Hygiene Interventions to Reduce Diarrheal Disease Burden Am J Public Health 2007 97: 846-852, 10.2105/AJPH.2006.086207. Zsigmond Kósa, György Széles, László Kardos, Karolina Kósa, Renáta Németh, Sándor Országh, Gabriella Fésüs, Martin McKee, Róza Ádány, and Zoltán Vokó A Comparative Health Survey of the Inhabitants of Roma Settlements in Hungary Am J Public Health 2007 97: 853-859, 10.2105/AJPH.2005.072173. Marwan Khawaja and Rima R. Habib Husbands’ Involvement in Housework and Women’s Psychosocial Health: Findings From a Population-Based Study in Lebanon Am J Public Health 2007 97: 860-866, 10.2105/AJPH.2005.080374. Sônia Lansky, Elisabeth França, and Ichiro Kawachi Social Inequalities in Perinatal Mortality in Belo Horizonte, Brazil: The Role of Hospital Care Am J Public Health 2007 97: 867-873, 10.2105/AJPH.2005.075986. Mika Kivimäki, Debbie A. Lawlor, George Davey Smith, Anne Kouvonen, Marianna Virtanen, Marko Elovainio, and Jussi Vahtera Socioeconomic Position, Co-Occurrence of Behavior-Related Risk Factors, and Coronary Heart Disease: the Finnish Public Sector Study Am J Public Health 2007 97: 874-879, 10.2105/AJPH.2005.078691. Thomas W. Valente, Chich Ping Chou, and Mary Ann Pentz Community Coalitions as a System: Effects of Network Change on Adoption of Evidence-Based Substance Abuse Prevention Am J Public Health 2007 97: 880-886, 10.2105/AJPH.2005.063644. Coen H. van Gool, Gertrudis I.J.M. Kempen, Hans Bosma, Martin P.J. van Boxtel, Jelle Jolles, and Jacques T.M. van Eijk Associations Between Lifestyle and Depressed Mood: Longitudinal Results From the Maastricht Aging Study Am J Public Health 2007 97: 887-894, 10.2105/AJPH.2004.053199. Daniel Polsky, Sara J. Ross, Barbara L. Brush, and Julie Sochalski Trends in Characteristics and Country of Origin Among Foreign-Trained Nurses in the United States, 1990 and 2000 Am J Public Health 2007 97: 895-899, 10.2105/AJPH.2005.072330. Margaret A. Handley, Celeste Hall, Eric Sanford, Evie Diaz, Enrique Gonzalez-Mendez, Kaitie Drace, Robert Wilson, Mario Villalobos, and Mary Croughan Globalization, Binational Communities, and Imported Food Risks: Results of an Outbreak Investigation of Lead Poisoning in Monterey County, California Am J Public Health 2007 97: 900-906, 10.2105/AJPH.2005.074138. Kesha Baptiste-Roberts, Tiffany L. Gary, Gloria L.A. Beckles, Edward W. Gregg, Michelle Owens, Deborah Porterfield, and Michael M. Engelgau Family History of Diabetes, Awareness of Risk Factors, and Health Behaviors Among African Americans Am J Public Health 2007 97: 907-912, 10.2105/AJPH.2005.077032. Chantal Matkin Dolan, Helena Kraemer, Warren Browner, Kristine Ensrud, and Jennifer L. Kelsey Associations Between Body Composition, Anthropometry, and Mortality in Women Aged 65 Years and Older Am J Public Health 2007 97: 913-918, 10.2105/AJPH.2005.084178. Kathleen A. Cagney, Christopher R. Browning, and Danielle M. Wallace The Latino Paradox in Neighborhood Context: The Case of Asthma and Other Respiratory Conditions Am J Public Health 2007 97: 919-925, 10.2105/AJPH.2005.071472. Arleen F. Brown, Alfonso Ang, and Anne R. Pebley The Relationship Between Neighborhood Characteristics and Self-Rated Health for Adults With Chronic Conditions Am J Public Health 2007 97: 926-932, 10.2105/AJPH.2005.069443. Gilbert C. Gee, Jorge Delva, and David T. Takeuchi Relationships Between Self-Reported Unfair Treatment and Prescription Medication Use, Illicit Drug Use, and Alcohol Dependence Among Filipino Americans Am J Public Health 2007 97: 933-940, 10.2105/AJPH.2005.075739. Daniel J. Whitaker, Tadesse Haileyesus, Monica Swahn, and Linda S. Saltzman Differences in Frequency of Violence and Reported Injury Between Relationships With Reciprocal and Nonreciprocal Intimate Partner Violence Am J Public Health 2007 97: 941-947, 10.2105/AJPH.2005.079020. MARKETPLACE: MARKETPLACE Am J Public Health 2007 97: 948-950. JOB OPPORTUNITIES: JOB OPPORTUNITIES Am J Public Health 2007 97: 951-957. LETTERS AGENT-BASED MODELING: highly stylized environment.5 Whether this lattice can be bordered or unbordered (i.e., USE WITH NECESSARY CAUTION teaches us about drinking behavior is an em- moving off the right side puts you on the left pirical question.4 Similarly, the “bar”3(p2058) is side) and conversion can be asynchronous or Agent-based modeling—a tool employing nothing more than a probabilistic sink that synchronous (all agents determine the new multiple interacting agents to reveal emer- guarantees to attract the “drinkers” who in no agent type before all agents convert together). gent properties of systems that are not prop- way “chose to spend a greater portion of their I replicated a family of models with NetLogo erties of the individual agents themselves1— time at this site”3(p2059) (emphasis added). 3.1.1 (Center for Connected Learning and has made significant in-roads into many Ecological validity and simple face validity Computer-Based Modeling, Evanston, Ill) to social science disciplines,2 including public are also important concerns. In one instance, determine the likely characteristics of Gorman health. I congratulate Dennis Gorman and Gorman et al. sought to identify ecological et al.’s models, with good results (Figure 1). his colleagues on their effort to leverage components of drinking behavior that they (The “bar” model runs 20000 periods in ap- these new tools to address specific public suggest might be thought of as a college pop- proximately 40 seconds on a 1.6 Ghz Pentium health concerns.3 However, given the novelty ulation that moves from a specific site with a processor; models are available from the au- of agent-based modeling methodology and given probability each day, operationalized thor upon request.) This replication also the resistance of those favoring traditional as a random walk.3(p2056) However, each of helped me to sort out the mathematical error analytic methods,4 great care in application is these students will have his or her own sink in Gorman et al.’s Figure 13(p2056) (The ordi- necessary to increase the likelihood of ac- in the form of an apartment or a dorm room nary proportion for conversion from suscepti- ceptance. In this spirit, I offer a few concerns. that he or she should return to (at least on bles to drinkers, Most important, it is imperative to be clear most days). Gorman et al.’s random-walk di() di() about what agent-based models have to offer. method quickly produces probabilistic = , si()++ ri () di () ti() Gorman et al. claim that their “models dem- homelessness. onstrate that the basic dynamics underlying Finally, precision is required in specifying shown on the state diagram, rather than dou- social influences on drinking behavior are models and reporting results. For example, a ble this proportion as specified in the body shaped by contacts between drinkers and focused by characteristics of drinking environ- ments.”3(p2055) The offered models demon- strate no such thing. At most, the models provide insight into the spatial dynamics of agents following programmed rules that re- spond stochastically to other agents in a Letters to the editor referring to a recent Journal article are encouraged up to 3 months after the article’s appearance. By submitting a letter to the editor, the author gives permission for its publication in the Journal. 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