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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Analysis of hospital reviews through sentiment analysis: An approach to aid patients in the times of COVID-19 pandemic</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ankita Bansal</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Manoj Maurya</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Niranjan Kumar</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Siddharth Tomar</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Information and Technology, Netaji Subhas University of Technology</institution>
          ,
          <addr-line>Dwarka, New Delhi</addr-line>
          ,
          <country country="IN">India</country>
        </aff>
      </contrib-group>
      <fpage>228</fpage>
      <lpage>236</lpage>
      <abstract>
        <p>The COVID pandemic had over-stressed our healthcare system. This has affected the lives of both COVID and non-COVID patients, in the worst possible way. The patients are facing difficulty in getting proper medical care in time. The reason being the already stressed situation of hospitals and lack of proper information in the general population. The lack of information is amplified in the environment of fear and panic in the pandemic. We aim to use sentiment analysis of hospital reviews to provide relevant and important information about the operating conditions and current status of hospitals to the general public. Sentiment analysis applied to patient's reviews to quantify the direction and/or magnitude of the emotive content. Patient comments are segregated into different sections and analysis is done on these sections to quantify the positive or negative aspects of the reviews. This will allow us to give an overall rating to the hospital-based on key parameters that will help people to understand the hospital's current condition. The results established a strong relationship between the online reviews and the overall recommendation percentage of the hospitals. This information provides great value to the patients by allowing them to compare and select the best option. The information is more reliable and robust due to its dynamic nature.</p>
      </abstract>
      <kwd-group>
        <kwd>Sentiment analysis</kwd>
        <kwd>Natural language processing</kwd>
        <kwd>lemmatization</kwd>
        <kwd>web scrapping</kwd>
        <kwd>COVID-19 outbreak</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The end of the year 2019 has seen a spread of
COVID-19 coronavirus in China which infected a
large number of people all over the country [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
However, China was soon able to control the
outbreak, while COVID-19 spread to other
countries.
      </p>
      <p>
        At present, many countries can control the further
spread of COVID-19, from the pandemic, the
healthcare industry being one of them. while few
countries are still struggling to adopt efficient and
effective The study by Bartik et al. 2020 shows that
pandemic has led to a massive dislocation of small
businesses [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
In contrast, there have been few sectors that have
benefited. In the difficult times of COVID-19
Pandemic, our healthcare system has been
continuously operating above its capacity and is in
a stressed situation [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. This has not only affected
the healthcare workers but also patients who are in
immediate need of medical care. Patients have
faced great difficulty in getting access to hospitals.
The primary reason being overcrowding of
hospitals but another significant reason that can be
resolved is the lack of information about the
hospitals among the general populous. This
problem has serious consequences on not only
COVID-19 patients but also other non-COVID
patients who are required to take extra precautions
in this pandemic as their current health puts them at
higher risk [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The non-COVID patients are also
finding serious difficulties in getting treatment due
to a lack of proper information about hospitals and
details regarding their current status [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. To get the
precise information about hospitals like the
availability of beds, availability of ventilators, and
any other such data, people generally follow the
traditional process of question-answers where they
ask from their friends, acquaintances, and other
people who might have used the facilities of the
particular hospital or may know about the hospital.
Nowadays, the more popular method is to read
reviews of the hospitals posted by the patients and
other stakeholders on various blogs and social
networking websites which are easily accessible on
the internet [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Patients share their opinions,
suggestions, and other thoughts, which may be
either favorable or unfavorable on various review
sites. However, these reviews are largely
unstructured, contain sarcasm, language slangs, etc.
Hence, it becomes necessary to understand these
reviews properly to derive meaningful insights
from them, which is the basic idea behind
Sentiment Analysis [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Sentiment analysis is a
domain that classifies reviews, comments, or
opinions into two basic and intrinsic emotional
indicators namely positive and negative [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
Sentiment analysis means the understanding of the
emotional essence of any text and the evaluation of
the nature of opinion of the text [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Nature can be
either on the extremes of good and bad or just
neutral [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Sentiment analysis has been used on
the reviews of movies, hotels, restaurants, etc. to
help customers to choose according to their
requirements, but work on the application of
sentiment analysis on the reviews of hospitals is not
much and thus it is an area to explore. The manual
way of filtering out reviews associated with a
hospital's status and the condition is not scalable
and also has reliability issues. To automate the
process of categorizing the sentiment from reviews
or posts, we analyze the text then perform natural
language processing along with various
computational techniques [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
      </p>
      <p>In this paper, the authors have developed a
methodology to extract reviews on 184 hospitals
from mouthshut.com and thereby apply sentiment
analysis on the reviews to gain meaningful insights.
In other words, the authors aim to conclude the
patient's reviews collected from some review
specific sites. In this work, the authors have</p>
      <p>From this study, the authors found that the
sentiment analysis of online reviews can provide
reliable information on hospitals. This information
can be very useful for patients as it helps them
compare and choose what's best for them. The
analysis result also helps hospital administration to
improve the current services according to the needs
of the patients. Sentiment analysis is a very useful
tool for gaining insight into a patient's opinions.
This can also be generalized for consumers. A large
number of companies including the health sector as
well are using this tool for providing a better service
to their customers. After analysis of the review, we
addressed the task of classifying given reviews as
positive, negative, or neutral. The task is complex
in nature due to the inherent complexity of the
natural language constructs as there are many ways
to indicate positive and negative views in natural
language.</p>
      <p>The contributions of this paper are:
1. Development of a general approach towards
Sentiment Analysis for any product or services
based on online reviews.</p>
      <p>2. Collection of nearly 14121 reviews from
mouthshut.com of 184 hospitals.</p>
      <p>3. Established a relationship between the
patient's review for the hospital and overall
recommendation for the hospital.</p>
      <p>4.Classification of a given review as positive,
negative, neutral.</p>
      <p>5. Provide the overall rating (recommendation
percentage) of each of the hospitals so that the
customers/patients can draw a comparison amongst
them.</p>
      <p>
        The task of Sentiment Analysis of hospital reviews
mainly includes the following steps in sequence –
preprocessing [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], feature extraction which is
followed by the selection of the relevant features
[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], classification [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ], and finally the result
analysis. Preprocessing includes removing any
error present in the review which is very important
for the task of proper and accurate classification of
text. Feature Extraction identifies the features that
are essential and then these features are stored in
the feature array. Different types of feature
extraction methodologies exist and in this paper,
the authors have used machine learning-based
feature extraction methods. Finally, the analysis
involves the overall calculation of the percentage
for the hospital. This percentage is based on the
polarity of all the reviews of the particular hospital.
can classify the consumer's emotions about the
product or service in question [
        <xref ref-type="bibr" rid="ref16 ref17 ref18">16,17,18</xref>
        ].
      </p>
      <p>The paper is organized in a total of ten sections.
The next section discusses some works already
done in the field of sentiment analysis along with
other works related to the analysis of hospital
reviews. Following this, section 3 describes the
collection and structuring of the dataset for the
hospital and its reviews. Section 4 discusses the
methodology of the work. The results are presented
in section 5. The next section discusses the practical
implications of the work. The final section contains
the epitome of paper and future work is discussed.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <p>
        Sentiment Analysis is popularly used for providing
ratings to movies, hotels, restaurants based on the
reviews provided by the customers on different
review websites, blogs, online groups, etc. For
example, many approaches involve the use of using
a tree kernel-based model for the classification of
the polarity for Twitter tweets into three classes
namely: positive, negative, and neutral. This can
also be used for gauging public sentiment regarding
any particular event, news, etc. The random forest
method is often used to attain a very high accuracy
for predicting the overall reception and popularity
of books by the reviews. In addition to this, few
studies have used sentiment analysis in the field of
healthcare. For example, the authors of paper [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]
demonstrated the use of sentiment analysis for
analyzing a person's online posts, tweets, remarks,
etc. regarding their experiences in a hospital or any
health-care-related institution. And the new
approach might be a better alternative than the
traditional methods such as surveys that were
previously associated with measurements
regarding customer satisfaction and feedback.
From this survey, we appreciated the importance of
our proposed work which is based on the idea of
using sentiment analysis on hospital reviews to
collect reliable and dynamic data on working
conditions of hospitals.
      </p>
      <p>The gathered results will be very beneficial for the
general public who are facing a serious lack of
reliable and dynamic information on the condition
of hospitals. The current virus-pandemic situation
had amplified the problems faced by the public.
Reliable information will help both COVID and
non-COVID patients. This will also reduce the
stress on our healthcare system which might face
problems because of false information in public.
This work opens up a new dimension of
possibilities where sentiment analysis can not only
be used as feedback by the healthcare system but
also provide public reliable and right information
on hospitals and other such infrastructures. The
dynamic nature of information ensures future
reliability and also makes our results more robust.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Data collection and preprocessing</title>
      <p>Data collection is done by the method of web
scraping. It is a method used to fetch large volumes
of data from multiple websites. Web scraping
automates the process of data gathering and data
can be gathered in multiple formats. We extracted
the hospital reviews data from India's largest
review website mouthshut.com. Python was used
for data extraction as it has efficient tools for web
scraping.</p>
      <p>Web scraping is done using the Beautifulsoup
library and the Request library of python. We have
extracted the review data from the website and
stored it in a JSON file. Thus, the process of data
collection can be summarized in three main steps:
(1) pairing of HTML websites, (2) extraction of
required data, and (3) storing of data. A total of
14121 reviews of 184 hospitals are collected from
well-known and established review sites.After
gathering data, we generally need to clean and
reorganize the data as the collected data is not well
structured and needs some processing before it
becomes ready to use. We organized the raw data
after cleanup into a key-value pair where key
attribute indicates the Hospital's name and the value
- attribute represents the reviews of the particular
hospital.</p>
      <p>In this study, preprocessing of the data is done by
(1) Removing HTML tags and URLs, (2)
Correcting spelling errors. Reviews may contain
bold /underlined/ italic words to emphasize the
meaning of some words or sentences. Different tags
in HTML are used for this purpose, &lt;b&gt; for bold,
&lt;u&gt; for underline and &lt;i&gt; for italics. However,
while analyzing the reviews, such emphasizing is
of no use as they do not provide any useful
information towards the sentiment, thus, they are
removed. Similarly, punctuation marks, special
characters, white spaces, stop words, etc. are also
removed during preprocessing. In addition to this,
there may be some spelling errors in the review
which can result in deviation from correct analysis.
TextBlob is a Python library for processing textual
data.</p>
      <p>We used the correct () method in the TextBlob
library to attempt spelling correction. After
removing all the unnecessary HTML tags and
correcting the spelling mistakes, the whole review
is separated into two parts, viz. the review title &amp;
the review body.</p>
      <p>The review title gives the whole gist of the review
and hence can be used to get the whole sentiment
of the review. So to analyze the sentiment of the
review we first find the polarity of the review title
and if and only if the polarity is neutral then we
process the review body for finding the polarity.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Methodology</title>
      <p>If we delve into the Sentiment analysis, it also
involves the understanding of different emotions
conveyed by the patient. These emotions can be
regarding any of the following feelings such as
anger, gloom, joy, confidence, shock, pity, panic,
and expectation. In the following section, we
explain in detail, the algorithm used for polarity
calculation and assigning the positive, negative,
and neutral rating to each hospital.</p>
      <p>The coding has been done in Python using the
module NLTK (Natural Language Toolkit) which
is used for natural language processing. Figure 1
represents the main processing that is applied to the
preprocessed data. It involves the polarity
calculation to find the sentiment of the review. The
output is organized and stored in a database that is
analyzed for the final results and conclusion.
4.1</p>
      <p>Steps used to conduct the review analysis
The proposed algorithm is represented by the
following steps:</p>
      <p>Step 1: Break the review into sentences i.e.
Tokenization.</p>
      <p>By our methodology, the sentiment analysis can
only be done for each sentence of the review and
therefore we need to break the review into
sentences. We Apply the SentenceTokeniser() to
break each review into sentences as follows:
nltk.tokenize.punkt.PunktSentenceTokenizer()</p>
      <sec id="sec-4-1">
        <title>Step 2: Analyzing the negation sentences</title>
        <p>For sentiment analysis, the algorithm must know
the structure of the sentence. For example, the
sentence can be complex and may include
comparison, contradiction, negation, or irony.
Negation can be of a localized nature, it can of
longrange or it can be the negation of the subject. To
analyze these sentences, we mark the words which
have changed their meaning due to the tone of the
sentence. For eg. If the sentence is stated as “The
hospital is not good” the sentiwordnet will give this
a positive polarity due to the presence of "good" in
the sentence. After marking the negation of the
sentence it will become "The hospital is not
good_NEG” now the sentiwordnet will give this
sentence a negative polarity due to the presence of
“good_NEG”. The interpretation of the word
changes for the sentiwordnet after it is marked as
negation. Negation analysis is done as follows:
nltk.sentiment.util.mark_negation(sentence)
For example, consider the following original
sentences and their negation analysis.</p>
        <p>Original Sentence ⇒ Sentence after negation
analysis(“polarity”)
not good ⇒ not good_NEG (“negative”)
does not look very good ⇒ does not look_NEG
very_NEG good_NEG(“negative”)
no one thinks that it’s good ⇒ no one_NEG
thinks_NEG that_NEG it's_NEG
good_NEG(“negative”)
Step 3: Tagging words by their syntactical nature
Part of Speech (POS) tagging involves tagging the
word in a corpus to a congruous part of a speech tag
based on its grammatical definition. We have
attached the PosTag such as adjective, noun, adverb
&amp; verb with the word in the sentence. The noun
phrases generally correspond to product features,
adjectives refer to opinions, and adverbs are
generally used as modifiers to represent the degree
of expressiveness of opinions.</p>
      </sec>
      <sec id="sec-4-2">
        <title>Step 4: Lemmatization</title>
        <p>It is a text normalization technique in the domain of
Natural Language Processing that is used to prepare
text &amp; words for further processing. It refers to
performing things in the right way along with the
use of a vocabulary and morphological analysis of
words, aimed for the elimination of inflectional
endings only and to return the base form of a word,
which is called a lemma. For example:“playing”-&gt;
Lemmatization -&gt; “play”
“plays”-&gt; Lemmatization -&gt; “play” and
“played”&gt; Lemmatization -&gt; “play”.</p>
        <p>Step 5: Repeat steps 6-7 until each sentence of the
review is iterated.</p>
        <p>Step 6: Maintain three counters: the first counter
stores the positive reviews count, the second
counter stores the negative reviews count, and the
third counter stores the neural reviews count.
Step 7: Polarity Calculation using SentiWordNet
The sentiment analyzer uses words, their meanings,
alternative words, polarity of each word, and
association intensity level with each word words in
a sentence. The polarity of the sentence is usually
based on the meaning of words. However, the
negation (for negative sentences only) changes the
meaning of the words and polarity of the sentence
in reverse order. Now check the orientation of the
review title using SentiWordNet. If the orientation
is positive or negative, then update the respective
counter. If the orientation is neutral, then check the
orientation of the review body and update the
respective counter.</p>
      </sec>
      <sec id="sec-4-3">
        <title>Step 8: Calculating the final results</title>
        <p>The polarity data is calculated for every review and
a final polarity value of each hospital is computed
by taking the summation of the polarity value of all
the reviews for a particular hospital. Then using this
data, we finally calculate the recommendation
percentage of every hospital according to the
reviews. Recommendation percentage is calculated
by dividing the number of positive reviews by the
total number of reviews and then multiplying by
100 for percentage.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Results analysis</title>
      <p>Here we evaluate and analyze the results. The
results are represented in the terms of quantity of
positive ratings, the number of negative ratings, the
number of neutral ratings, and the recommendation
percentage in Table 1. The amount of positive
rating represents the number of good ratings given
by the user in their review and the number of the
negative rating represents the quantity of poor
rating given by the user in their review. Then finally
the recommendation percentage is indicated for the
hospital-based on the polarity of overall reviews of
the hospital. Recommendation percentage is
calculated by dividing the number of positive
reviews by the total number of reviews and then
multiplying by 100 for percentage.</p>
      <p>As discussed, we collected 14121 reviews of 184
hospitals from mouthshut.com a well-known and
established review site. Due to space constraints, it
is not feasible to represent the result values of all
the 184 hospitals. Therefore, concerning all the
reviews of 184 hospitals, we report the overall
negative, positive and neutral ratings which are
11427, 2545, and 149 respectively. To show the
results corresponding to the hospital names, we
selected a few hospitals out of a total of 184
hospitals. For selecting a few hospitals, we have
divided the hospitals into 3 categories and have
represented the results for only the hospitals which
fall in these categories. Hospitals are categorized
based on their recommendation percentages as
follows:
Category 1: Hospitals with a recommendation
percentage between 80 to 100
This category represents the ‘Best’ class which
includes the most recommended hospitals.
Category 2: Hospitals with a recommendation
percentage between 70 to 79 This category
represents the 'Average' class.</p>
      <p>Category 3: Hospitals with the recommendation
percentage between 0 to 69 This category
represents the ‘Poor’ class which includes the least
recommended hospitals.</p>
      <p>The hospitals are divided into three categories
according to the scatter plot shown in figure 2
which represents the overall distribution of the
hospitals over the recommendation percentage.
This trend line can further be used as a benchmark
that can be tested against other hospital’s
recommendation percentages. This benchmark also
allows us to further categorize hospitals based on
their relative recommendation percentage which
can also be used to generate relative ranking for the
hospitals in the dataset. Since the ranking in
general, it can also be used on newly included data
to expand the scope of the dataset and also increase
the reliability of the methodology.
Columbia Asia Hospital - Malleshwaran</p>
      <p>Bangalore</p>
      <p>Park Hospital - Gurgaon
Iswarya Fertility Test Tube Baby and Research
Centre - Coimbatore
The results are also represented in the form of a pie
chart in figure 3. The pie chart is used for the
representation of sentiment distribution of reviews.
The chart indicates that neutral reviews are only a
very small fraction which completely coincides
with the general nature of opinions and reviews in
the online community and also with commonly
observed patterns of distribution of sentiments of
opinion by the general populous. The large
percentage of positive reviews also is following our
average recommendation percentage of the
hospitals. Both scatter plot (for distribution of
hospitals on the recommendation percentage) and
pie chart (for distribution of sentiment of the
reviews) validated the integrity and reliability of
the dataset used in this paper to demonstrate the
methodology for sentiment analysis on the hospital
reviews by the patients.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion &amp; Future Work</title>
      <p>Sentiment analysis is an ever-expanding field and it
needs a lot of work to mature as a domain of study
This paper has emphasized the importance of
review analysis for a multitude of benefits for both
patients and the healthcare sector itself. It can help
patients by providing relevant and reliable data for
both COVID and non-COVID patients. It also helps
in revealing the weak links of the overall system
which need immediate improvement. These
improvements will not only help patients but also
allow hospitals to increase their operational ability
in stressed pandemic situations. The general
method involves three main sections namely: data
collection, pre-processing, sentiment analysis of
reviews, and finally analysis for the
recommendation rating of the hospitals. The data
collection is done through web-scraping using
python and preprocessing involves the removal of
non-essential components of the collected data.
Then using sentiment analysis, we find the
sentiment of the review which can be positive,
negative, or neutral. Then in the final step, we
calculate the final recommendation rating of the
hospital by finding the percentage of positive
ratings based on the total no of reviews.
large data -set and its dynamic nature. This result
can also provide hospital administration with the
patient's valuable feedback which will allow them
to improve the quality of service at the hospital.
The approach discussed in this paper also has some
implications for other sectors especially the service
sector where the quality of services and its
perception is the most important metric for the
company involved. This paper established a strong
relationship with the online reviews and how its
analysis has applications for both the consumers
and the company which is providing the services.
And for the provider company, the analyzed data
can provide important insight for upgrading the
standard of the facility. The approach may be
further extended to analyze the different aspects of
the service or product in question. This may be
achieved with slight modification in the
methodology and the same dataset provided that the
dataset has diverse reviews covering the different
aspects of the product or service. This can give us
more detailed insight into different aspects or
attributes of the product.</p>
      <p>Considering the healthcare industry as an example
we can modify the approach and try to find the
aspect-based rating for different attributes of the
hospital. Different aspects related to hospitals such
as infrastructure, food quality, economic expense,
etc. can also be categorized and rated. One
drawback is that this method will need a more
diverse dataset or extra dataset to augment the
analysis</p>
    </sec>
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