The application of Poisson hidden Markov model to forecasting new cases of congenital hypothyroidism in Khuzestan province
Abstract
Background & Aim: Congenital hypothyroidism (CH) is one of the most common endocrine diseases and is a major cause of preventable mental retardation. Early diagnosis of CH can help prevent future diseases. Although time series techniques are often utilized to forecast future status, they are inadequate to deal with count data with overdispersion. The aim of this study was to apply Poisson hidden Markov model to forecast new monthly cases of CH disease.
Methods & Materials: This study was based on the monthly frequency of new CH cases in Khuzestan province of Iran, from 2008 to 2014. We applied stationary Poisson hidden Markov with different states to determine the number of states for the model. According to the model, with the specified state, new CH cases were forecast for the next 24 months.
Results: The Poisson hidden Markov with two states based on Akaike information criterion was chosen for the data. The results of forecasting showed that the new CH cases for the next 2 years comforted in state two with the frequency of new cases at 6-18. The forecast mode and median for all months were 12 and 13, respectively. Each state is explained by each component of dependent mixture model.
Conclusion: Our estimates indicated that state of frequency of CH case is invariant during the forecast time. Forecast means for the next 2 years were from 13 to 14 new CH cases. Furthermore, forecasting intervals were observed between 7 and 25 new cases. These estimates are valid when the general fertility rate and crude birth rate were been fixed.
Valizadeh M, Mazloomzadeh S, Niksirat A, Shajari Z. High incidence and recall rate of congenital hypothyroidism in Zanjan province, a health problem or a study challenge? Int J Endocrinol Metab 2011; 9(4): 338-42.
Namakin K, Sedighi E, Sharifzadeh G, Zardast. Prevalence of congenital hypothyroidism in south Khorasan province (2006-2010). J Birjand Univ Med Sci 2012; 19(2): 191-9. [In Persian].
Ordookhani A, Mirmiran P, Najafi R, Hedayati M, Azizi F. Congenital hypothyroidism in Iran. Indian J Pediatr 2003; 70(8): 625-8.
Rastogi MV, LaFranchi SH. Congenital hypothyroidism. Orphanet J Rare Dis 2010; 5: 17.
Yordam N, Calikoglu AS, Hatun S, Kandemir N, Oguz H, Tezic T, et al. Screening for congenital hypothyroidism in Turkey. Eur J Pediatr 1995; 154(8): 614-6.
Feizi A, Hashemipour M, Hovsepian S, Amirkhani Z, Klishadi R, Rafee Al-Hosseini M, et al. Study of the efficacy of therapeutic interventions in growth normalization of children with congenital hypothyroidism detected by neonatal screening. Iran J Endocrinol Metab 2011; 13(6): 681-9. [In Persian].
Fazekas M. Application time series models on medical research [Online]. [cited 2014]; Available from: URL: http://m.ludita.uninke.hu/repozitorium/handle/11410/109?show=full
Cooper B, Lipsitch M. The analysis of hospital infection data using hidden Markov models. Biostatistics 2004; 5(2): 223-37.
Lu Y, Zeng L. A nonhomogeneous Poisson hidden Markov model for claim counts. ASTIN Bulletin 2012; 42(1): 181-202.
Nam L, Kaito K, Kobayashi K. A Poisson hidden Markov model for deterioration prediction of road asset system [Online]. [cited 2010]; Available from: URL: http://library.jsce.or.jp/jsce/open/00039/201011_no42/pdf/161.pdf
Antonucci A, de Rosa R. Time series classification by imprecise hidden Markov models [Online]. [cited 2011]; Available from: URL: http://people.idsia.ch/~alessandro/papers/antonucci2011e.pdf
Viviano LCM. Discrete or continuous-time hidden Markov models for count time series [Online]. [cited 2006]; Available from: URL: http://old.sis-statistica.org/files/pdf/atti/rs08_spontanee_10_4.pdf
Inge A. Hidden Markov models. Theory andsimulation [Thesis]. Stockholm, Sweden: Stockholm University; 2013.
Zucchini W, MacDonald IL. Hidden Markovmodels for time series: an introduction using R. Boca Raton, FL: CRC Press; 2009.
Murakami J. Bayesian posterior mean estimates for Poisson hidden Markov models. Computational Statistics & Data Analysis 2009; 53(4): 941-55.
Paroli R, Redaelli G, Valizadeh M. Poisson hidden markov models for time series of overdispersed insurance counts [Online]. [cited 2000]; Available from: URL: http://www.actuaries.org/astin/colloquia/porto_cervo/paroli_redaelli_spezia.pdf
Olteanu M, Ridgway J. Hidden Markov models for time series of counts with excess zeros [Online]. [cited 2012]; Available from: URL: https://hal.inria.fr/file/index/docid/655588/filename/esannV2.pdf
Green PJ, Richardson S. Hidden Markov models and disease mapping. Journal of the American Statistical Association 2002; 97(460): 1055-70.
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Issue | Vol 2 No 1 (2016) | |
Section | Original Article(s) | |
Keywords | ||
Congenital hypothyroidism Poisson hidden Markov forecast Khuzestan |
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