While the payoff could be big-Atlanta claims it took in $5.1 billion from the 1996 Games-each city has huge political and logistic hurdles to clear.
A number of methodological and logistic hurdles remain to link hospital quality improvement systems to outcomes.
Contact tracing after potential transmission of infectious diseases in public ground transport is often hampered by logistic hurdles; tracing passengers may be limited or even unfeasible since passenger data (eg, name, telephone number, email address) in metros, trams and short-distance bus trips are not collected.
Next-generation sequencing offers opportunities for genetic testing but is often complicated by logistic and interpretative hurdles.
We only report the results of the logistic component of the Hurdle model in this paper; the zero inflated Poisson regression gave similar conclusions (data available from authors).
Discrepancies between the study by van Doorslaer et al. and our study are particularly worth investigating given that their study used the same data and the same type of statistical modeling approach: a two-part "hurdle" model (logistic and zero-truncated negative binomial regression models).
The results from the logistic component of the Hurdle model (table 4) show that, for both all-cause and cardiovascular admissions, the significant differences found in the original SPHERE study at 18 months persist in the 12-month equivalent analysed here, but are not apparent at 24, 36, 48, 60 or 72 months.
Hence, the reality of logistic, economic, and cultural hurdles for fortification leaves the natural and bioavailable mineral content in food, and in plants in particular, to be the major, and sometimes the only, consistent mineral supply for a large part of mankind (White and Broadley, 2009; Bouis and Welch, 2010).
Legal and administrative hurdles, regulatory issues and logistic problems have meant that the W.H.O. has been unable to deliver vaccines to developing countries at the time they most needed them, when the disease was peaking.
A hurdle model with a generalised logistic model in the first part is proposed by Gurmu (1998) and a modified second part in the two-part model is suggested by Mullahy (1998).
