Appunti Elementi di biostatistica

However, representativeness can be a concern as online respondents may di er from

o ine ones.

When conducting web-based market research, interviews can be administered to

individuals or groups, depending on the research objectives. Self-administered

questionnaires, with or without assistance, can be used, or researchers can conduct

remote interviews using the web platform. Interviews can be synchronous (real-time) or

asynchronous (allowing respondents to provide information at their convenience).

Overall, web surveys o er various approaches and methodologies for collecting data,

each with its own strengths and limitations.

Economic bene ts of web survey research

Web surveys o er several advantages over traditional data collection modes. They allow

for signi cant economies of scale, reduce eldwork time, and provide a cost-e cient

means to reach low-incidence population segments. Web surveys are known for their

ability to collect information quickly and inexpensively from a potentially large group of

people.

However, the focus on cost-e ectiveness sometimes overshadows other important

aspects of web surveys, including their potential drawbacks. It is crucial for researchers

and companies to select the most appropriate data collection approach based on their

research objectives, considering factors beyond cost alone.

ffl ff fi ff ff ff fi fi ff ff ff fi fi

fi fi fi ff ffi

In some cases, researchers may opt for mixed-mode approaches, combining web

surveys with traditional modes of data collection. This hybrid approach can yield

remarkable results both statistically and economically. By starting with a less expensive

mode like web surveys, researchers can complete a signi cant number of interviews at a

lower cost. They can then switch to a more expensive mode, such as computer-assisted

telephone interviewing (CATI), to improve completion rates.

Overall, it is important to strike a balance between cost considerations and other

important factors when choosing a data collection approach. Mixed-mode surveys can

o er advantages that may not be achievable through a single data collection mode,

providing more exibility and better outcomes for research objectives.

Non-economic bene ts of web survey research

Web surveys o er several signi cant bene ts beyond economic considerations. Some of

the key advantages include:

Fast data capture turnaround: Web surveys allow for quick data collection thanks to

automatic questionnaire delivery, immediate availability of respondent data in electronic

format, and direct communication between respondents and the survey management

software.

Higher response rates: Web surveys generally yield higher response rates compared to

traditional modes, except for self-selection web surveys. Response rates for web panel or

community surveys typically range from 7% to 40%, depending on factors such as

recruitment, sampling framework, research topic, reminders, and incentives.

Geographically representative samples: Web surveys provide well-distributed samples

across di erent geographical areas, making them more representative than traditional

modes such as PAPI or CAPI, which often result in skewed samples. Web surveys enable

the inclusion of rural respondents and speci c population segments, resulting in more

diverse and representative samples.

Multi-country and multi-language capabilities: Web surveys can easily collect data from

di erent countries or multi-language territories. Data collection platforms can administer

ff ff ff ff fl fi fi fi fi fi

questionnaires in the respondent's preferred language and provide editing and analysis

features to monitor eldwork progress and identify potential issues.

Cost-e cient access to low-incidence or hard-to-reach populations: Web surveys o er a

cost-e ective means to reach population segments that are di cult or expensive to

access through traditional data collection modes. Remote rural areas, night shift workers,

managers, and speci c interest groups can be e ciently targeted through web surveys or

thematic communities, minimizing recruitment costs.

Convenience and anonymity: Web surveys provide convenience to respondents, allowing

them to complete the questionnaire at their preferred time and location. Respondents can

interrupt and resume the survey as needed, accommodating busy schedules. Anonymity

in web surveys eliminates potential biases introduced by interviewers and encourages

respondents to provide honest and accurate answers, especially for sensitive topics.

Reduced input errors and misinterpretations: The absence of interviewers in web surveys

reduces the likelihood of input errors or misinterpretations during the data input process.

Respondents directly enter their answers, reducing the chances of errors compared to

traditional modes. Quality checks and consistency measures can still be implemented to

ensure data integrity.

Direct relationship between respondents and researchers: Web surveys facilitate a closer

relationship between respondents and researchers. Feedback from respondents can be

collected, enabling researchers to improve questionnaire quality, establish trust, and

enhance survey methodologies. Respondents appreciate the opportunity to provide

feedback and feel listened to.

Inclusion of multimedia content: Web surveys allow for the inclusion of multimedia

elements such as images, video clips, audio clips, and interactive exercises. This feature

is particularly useful when text alone is insu cient to capture the context or when

multimedia elements are integral to the research objectives. Multimedia enhances

respondent engagement and provides more accurate data collection.

Flexible and powerful data collection software: Web surveys employ exible and

advanced data collection and management software. This software enables complex

questionnaire structures, personalized questionnaires, adaptive methodologies, and the

integration of past survey data from databases. Personalization enhances respondent

attention, optimizes data collection e ciency, and supports interactive methodologies.

Overall, web surveys provide a range of bene ts, including fast data capture, higher

response rates, representativeness, cost-e ciency for hard-to-reach populations,

convenience, anonymity, reduced biases, direct respondent-researcher relationship,

multimedia integration, and exible software capabilities. These advantages make web

surveys a valuable research mode with diverse applications in various domains.

Main drawbacks of web survey research

Web surveys o er advantages over traditional data collection methods, but they also have

limitations. Critics argue that web surveys may not always produce trustworthy

information and that researchers should be cautious when using them.

Web surveys are not suitable for all projects and should be chosen carefully. However,

technological advancements, statistical improvements, infrastructure development, and

social changes have made web surveys more feasible for a wider range of projects over

the past decade.

One of the early criticisms of web surveys was the low internet penetration in the target

population. However, the growing spread of the internet, especially in developed

countries, has made online surveys valid for key target populations. Despite this, there are

still population segments, such as the elderly, with low internet usage.

Representativeness is a concern in web surveys. There are three types of internet

surveys: those related to internet users, those focusing on a general statistical population,

ff ffi ff fi fi fl ffi ffi ffi fi ffi ffi fl ff