Reviewer ’s report  
 
Title: Loneliness among mothers raising children under the age of 3 years and predictors with  
special reference to the use of SNS: A community -based cross -sectional study  
 
Version: 0 Date: 21 Feb 2017  
 
Reviewer: Aya Ishiguro  
 
Reviewer's report:  
The present study inve stigated the factors associated with loneliness in mothers with infants under 
3-years of age, using the cross -sectional self -reported questionnaire survey. As a result of the 
multiple regression analysis, the risk factors, including low economic stability,  sparse social 
relationship with others, low scores on the Internal Working Model Scale (IWMS) which is 
strongly correlated with loneliness, more than 3 hours dairy use of smartphones, and a high 
likelihood for mood and anxiety disorders were significantly  detected.   
These findings may contribute to the further understanding of the cause of mothers' child abuse, 
depression, and deterioration in their health which was mentioned in the introduction based on the 
previous studies.  
However, some major and minor  flaws should be addressed for better understanding.  
 
Major comments  
1.P15 L236 and P18 L304 and Table 6  
There was inconsistency between your manuscript and table.  
Which is accurate result, the term of low economic stability in the manuscript (P15 L236) or  
estimated value of somewhat stable ( -3.35) and somewhat unstable ( -2.47) in table 6 (subjective 
economic status)? According to the result in the table, they were negatively associated with the 
Loneliness Scale score in the subjective economic status. This  may be confusing to the reader.  
 
2.Table 6, Main result  
As with the smartphone use in Table 6, it is questionable that the variable of "do not own a 
smartphone" was used for the reference to assess the association because those who didn't have a 
smartphon e should be differentiated from those with one. Theoretically, the variable of <30 
min/day can include those who didn't use a smartphone at all, so that I suggest the multiple 
regression analysis be performed with the variable of <30 min/day used as refere nce.  
In addition, I would suggest that you compare people who didn't have any communication tool 
including traditional cell phone, smartphone, tablet, and personal computer with participants who 
have at least one of them.  
 
 
Minor comments  
1.P7-8, About pa rticipants  
Were all mothers those who came to the health check -ups during the period given the 
questionnaires, or were some of them recruited for the present study? If so, was the selection 
conducted randomly or non -randomly? The term of participants was c onfusing between the health 
check -ups and those in the study.  
 
2.P8, L138, About IWMS  
How was the score range of IWMS from 6 to 36 defined? I suggest that you mention which of 
higher or lower value is a worse score. Unlike UCLA Loneliness Scale in P9 L142 , it is difficult 
for some readers to understand whether the higher score of IWMS is correlated to loneliness, 
negatively or positively.  
 
3.P14, L230 -231 
Not only showing factors significantly associated, directionality of results should be indicated, like  
positive or negative association.  
 
4.Table 4, About communication device  
What is the number and the percentage of people who do not have either a traditional cell phone 
or smartphone? Some use traditional cell phone and others use smartphone, but there may be those 
who don't use any communication device at all.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
Yes 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
Yes 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
No 
Are you able to assess any statistics in the manuscript or would you recommend an additional 
statistical review?  
If an additional statistical review is recommended, please specify what aspects require further 
assessment in your comments to the editors.  
I am able to asse ss the statistic  
Quality of written English  
Please indicate the quality of language in the manuscript:  
Acceptable  
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