[dreaming] Data reliability?!

Hi everybody,
After reading the first two comments on the "Determinants ans mental health
effects..." I am afraid that my evaluation is drastically different. I read
the paper several times and each time I read it I was more confused. There
are too many questions related to the data presentation and data collection
procedure that cast some doubt regarding the meaning of the findings. The
following are just few examples to exemplify my points:
1. The scales for the frequency of dream recall in Figures 1 and 2 ranged
from 9 to 13, while the same data in Figure 3 range from 1 to 3 how come?
2. Similarly, the scale for depression scores range from -.9 to -1.2 while
the scores for anxiety range from -1 to 9? (Fig 4).
3. There is no information on the magnitude of the differences in dream
recall frequency between the so called traumatized and the so called non
traumatized subjects. Only data on "every night recallers" and "no
recallers" are provided.
5. There is no information on the number of subjects in each category of
traumatic events (Figures 1a 1b and 2). It is very  difficult to understand
these findings without some idea on the number of subjects in each
category. Likewise, no data on the number of subjects in the three
repression category groups are provided (Figure 3).
6. What are the definitions of frequent and infrequent dream recalls (every
night ? 6/7 nights? vs 0?, 1-2/7 nights???). Why the categories are
inverted in Figure 4a and 4b?
7. Why the same scale for the level of traumatic events in figure 4a and 4b
range from 0.4 to 0.9 in (a) and from 2 to 16 in (b)?
8. The differences between the traumatized and non-traumatized groups are
far from being clear. While there was no difference between the groups
regarding how frequently they were wounded, 12% of the trauma group vs 6%
of the other group reported losing a family member through death. There is
no mentioning of the kind of death, violent death? accidents? Since there
is a very substantial diffrence in life expectancy between the two regions
such a difference is no surprising.
These are just few of the problems.
How anyone can make any sense of the findings without sorting out these
issues?

I also found it particularly distressing that in the discussion section,
Dagan Lavie and Bliech (1991) study is cited as supporting the observation
that "the sleep of traumatized people is lighter.." while this study
reported precisely the opposite. It showed that paradoxically the sleep of
traumatized people was deeper...This paradoxical finding was just
replicated in an independent group of war related PTSD patinets (Lavie et
al , Biological Psychiatry, in press).

I await your advice how to treat these findings,

Peretz Lavie
Sleep Lab, Technion
Israel Institute of Technology