Background. The reform of mental health services needs to be guided by
an overall conceptual framework. Such a framework is important to avo
id many risks, including extrapolating from a specific service site to
other services, without taking into account local and regional variab
les. Methods. A conceptual framework, the 'matrix model', is proposed.
This model has been developed using the most relevant information tha
t is necessary for describing and interpreting mental health services
data as well as patient-based information. Results. The 'matrix model'
has two dimensions: the geographical, which refers to three levels (c
ountry, local and patient) and the temporal, which refers to three pha
ses (inputs, processes and outcomes). Using these two dimensions a nin
e-cell matrix is constructed to bring into focus critical issues for m
ental health services. The relevance of each level and each phase is b
riefly presented. Conclusions. The matrix is intended to assist clinic
ians, planners and researchers to deal with clinical phenomena, organi
zational issues, and research questions that share a degree of complex
ity that render inadequate analyses and the interventions made only at
one level. The matrix model applies particularly to mental health sys
tems of care that are provided with a public health framework, and is
less useful for contexts that consist of clinicians offering only one-
to-one treatments, within fragmented programmes of care.