Helmet designs were classified as full face, open face, half face
and those not designed for motorcycle use (non-motorcycle helmet),
such as ‘sun helmet’, construction helmet, combat helmet
and others (see Fig. 1 for examples). Helmet use was classified as
‘correct use’ (chinstrap firmly fastened), ‘incorrect use’ (chinstrap
not firmly fastened or not fastened) and ‘no helmet use’. Road types
were classified as ‘city street’, ‘county road’, ‘provincial road’ and
‘national road’ according to designations from the city authorities.
The “city street” is unique to the urban settings and the other 3
types of road are characteristic of rural settings.
2.2.3. Observers training and audits
Observers were recruited from local colleges. Prior to data collection,
the 10 field observers attended 1 day of intensive training
and were trained in techniques to observe the correct use of helmets
at the roadside observational sites. The observers worked
in teams of two, observing the same motorcycle and recording
data independently on separate data collection forms. Teams were
rotated throughout the training to ensure that each observer was
paired with every other observer. The inter-observer reliability for
each pair of observerswasat least 85% for both observed drivers and
passengers. On-site audits were made by the researchers during
data collection to ensure adherence to study protocols.