Data will be extracted from the MDVP database and hospital medical records. The MDVP database
consists of patients examined with MDVP in the Department of ORL-HNS' Larynx-Pharynx clinic
of Dr. Cipto Mangunkusumo Hospital, Jakarta.
Voice evaluation for all patients in Dr. Cipto Mangunkusuomo Hospital was done using the
Multidimensional Voice Program (MDVP) 4500 produced by Kay Elemetrics Corp installed on a
personal computer. The patients were asked to emit vocal sounds /" a "/ using the tone and
intensity of everyday speech. The physicians are obliged to give an example first. The
patient's voice was then recorded using a microphone connected to a computer with the MDVP
program. Sounds were recorded in a quiet room for at least 3 seconds with the microphone 10
cm from the patient's mouth. The MDVP program will directly analyze the recorded sound. Sound
recording is done 3 - 5 times, and the best sound acoustic analysis results are used as the
final result. The results are then kept in the program's database inside the computer.
Patients who attend the Larynx-Pharynx clinic for MDVP evaluations are usually those who
comes for post-treatment monitoring (e.g., post-laryngoplasty), had been diagnosed with a
voice disorders, and or by personal or physicians' request. There are various reasons why
patients are being assigned to MDVP evaluations - and all of this information will be
gathered and used as a consideration during data analysis. For the sake of practicality, the
researcher will only extract MDVP data from the past five years. Other considerations will be
made to ensure that the data extracted will represent a reliable comparison between
occupation status and how it affects MDVP parameters (see more in "Criteria for subjects").
The study will use total sampling, where all available data that fits the inclusion criteria
will be used for analysis.
Inclusion criteria
Patients had their medical records and MDVP data available in dr. Cipto Mangunkusumo
Hospital, Jakarta
Patients are active workers in Indonesia on the time of MDVP evaluation
Patients are above the age of 18
Patients can be either an occupational or non-occupational voice users Exclusion
criteria
Patients with incomplete occupational data
Patient with incomplete MDVP results
Data obtained from the database will be evaluated in SPSS v20 software and analysed to
produce descriptive and inferential statistics. The inferential statistics will consist of
univariate analysis and bivariate analysis (between two variables). All numeric data will be
tested for normal distribution using Kolmogorov-Smirnov.
Univariate analysis will be done to see the average, distribution, and frequency of all
variables/outcomes which include the participants' demographic information and MDVP
parameters. MDVP parameters will be presented as mean score with its standard deviation (or
median with range). Bivariate analysis will be done to evaluate the significance between
occupational or non-occupational users to their MDVP parameters. Differences between groups
will be assessed using independent samples t-test (parametric) or Mann-Whitney
(non-parametric). If possible, multivariate analysis will also be conducted using Chi-Square
or Fischer test depending on the data distributions.