In addition to clarifying the specific methods and psy-
chological processes to be addressed by therapies for voices, there is a need to tighten conceptualization and
measurement of outcome. Psychological therapy trials
for
psychosis
have
been
criticized
for
using outcome
measures
of
symptom intensity used in antipsychotic
drug trials, not well suited to the aims of psychological
therapies of reducing impacts of symptoms on emotional
well-being and functioning rather than their occurrence.
The main voice-specific outcome measure used has been
the Psychotic Symptom Rating Scales (PSYRATS)
(see
Woodward et al, this issue). Although capturing a number
of
dimensions,
this
measure
has
limitations
in
giving
a
total
score
which
sums a series of
only modestly intercorrelated
scales,
and which
introduces
noise from
variables
not
targeted
by
therapy
(such as voice
frequency,
location,
and
extent
of
negative
voice
content),
while
individual
items are
comprised of
single 5-point ratings, likely to
lack sensitivity to change when used instead. Indeed, different
methods of
scoring have been used between trials
(single item, factor, or total score), reducing comparabil-
ity of findings. Better measures are needed to capture the
impact of voices on emotional well-being and functioning.
Multiple item measures
of
the subjective impact of
psychosis have been developed in recent years,
which
are likely to be more sensitive, but have yet to be reported
on in trials, and are not voice specific. The application of
these measures, and development of a voice-specific measure,
are
required
to provide
a more
accurate
estimate
of
targeted
voice
outcomes posttreatment
and at
follow-up.
This needs to be conducted in conjunction with more