Journal of Rehabilitation Medicine 51-8 | Page 85
J Rehabil Med 2019; 51: 621
LETTER TO THE EDITOR
COMMENTARY ON: “DEVELOPMENT OF GRIP STRENGTH DURING THE FIRST
YEAR AFTER STROKE”
We read with interest Roland Stock et al.’s article,
entitled, “Development of grip strength during the
first year after stroke” (1), and found the information
useful; the study and thought processes described
are interesting and useful. However, we consider
that the following methodological issues need to be
addressed.
First, the authors recruited patients with stroke, but
did not categorize the type of stroke included in the
study. Different types of stroke represent specific fea-
tures that signify the area of involvement. The outcome
of this study was grip strength, but this outcome is not
necessarily affected in all types of stroke, as should
have been explained (2).
Secondly, the authors mentioned ICC (3,1) for determi-
ning the degree of agreement between 2 raters, whereas
model 3 of the ICC indicates fixed raters with random
subjects and is hence termed a mixed model. To deter-
mine the degree of agreement between 2 raters, model
1 or 2 of the ICC should have been used (3).
Thirdly, the authors did not mention the normality
test for addressing whether data distribution is normal
(4). A further concern is the inappropriate representa-
tion of data in the Table. In Table I, the data is represen-
ted as means and standard deviations, which suggests
that it should be normal in distribution. However, range
is also used. Range is generally used with median
values, when the data is not normally distributed (4).
Apart from the aforementioned issues, this explora-
tory study is highly informative and might be very ef-
fective if the above-mentioned issues were highlighted.
Accepted Jun 5, 2019; Epub ahead of print Jun 24, 2019
Rajnee Mishra , BPT, (MPT)
From the Department of Pediatric and Neonatal Physio
therapy, Maharishi Markandeshwar Institute of Physiotherapy
and Rehabilitation, Maharishi Markandeshwar (Deemed to
be University), Mullana-133207. Haryana, India. E-mail:
[email protected]
REFERENCES
1. Stock R, Thrane G, Askim T, Anke A, Mork P. Development
of grip strength during the first year after stroke. J Rehabil
Med 2019; 51: 248–256.
2. Kenneth W, Lindsay I. Neurology and neurosurgery il-
lustrated. London: Churchill Livingstone; 2010, p. 258.
3. Portney LG, Watkins MP. Statistical measures of reliability.
In: Foundation of clinical research. 3rd ed. Philadelphia,
USA: FA Davis Co.; 2015, p. 590–591.
4. Portney LG, Watkins MP. Descriptive statistics. In: Foun-
dations of clinical research: applications to practice. 3rd
edn. Philadelphia; 2015, p. 390–391.
RESPONSE TO LETTER TO THE EDITOR FROM MISHRA
We thank Dr Mishra for her interest in our work and
her thoughtful comments. We agree that it would be
interesting to assess whether type of stroke (size and
precise localization of the lesion) would influence the
progression of grip strength. However, to compare
different types of stroke would require a high number
of participants, and analysing subgroups with regard to
type of stroke was beyond the scope of this exploratory
study. The main focus of our study was on the develop-
ment of grip strength during the first year after stroke.
Only patients with reduced strength were included
in the study. As stated in the paper, inclusion criteria
were persistent unilateral paresis, i.e., arm function
2–5 or hand motor function 2–4 on the Scandinavian
Stroke Scale.
Regarding the analysis of intra-class correlation
(ICC), it may have been more appropriate to use ICC (2,1)
than ICC (3,1) . Nevertheless, the resulting coefficients
were identical between the 2 methods and therefore
would not influence our conclusions.
As stated in the paragraph on statistical analysis, data
were normally distributed if mean values (standard
deviation; SD) were presented in the results. In Table
I, the range (i.e. the lower and upper range values) was
included to provide additional relevant information
about the study sample. This should not be confused
with making interpretations about the distribution of
the data.
Roland Stock, Gyrd Thrane, Torunn Askim, Audny Anke and
Paul Jarle Mork
From the Department of Physical Medicine and Rehabilita-
tion, Trondheim University Hospital, NO-7071 Trondheim,
Norway. E-mail: [email protected]
This is an open access article under the CC BY-NC license. www.medicaljournals.se/jrm
Journal Compilation © 2019 Foundation of Rehabilitation Information. ISSN 1650-1977
doi: 10.2340/16501977-2575