How to Optimize Surveys for SMS

SMS surveys are a useful method for conducting mobile research due to their ease, convenience, and wide reach – by administering surveys through SMS, people can answer questions without needing to download and install an application or pick up a phone call at a specific time. Using SMS, research is conducted remotely on an individual’s own mobile devices, with an initial opt-in message being sent first, followed by a series of questions that are answered by typing in answers and sending them back to the same number. SMS surveys are especially useful in emerging markets, where mobile penetration is continually growing, but smartphone and Internet penetration remains low, making online surveys less representative of a country’s population.

SMS surveys are also more cost-effective and faster than face-to-face or voice call interviews, though those modes can reach illiterate populations, which makes them beneficial for certain studies. While SMS surveys can be adapted for many research objectives, some basic guidelines should be followed when designing any SMS survey.

Tips for Designing SMS Surveys

Keep Questions and Answers Under 160 Characters: This rule is both the most important and most challenging to adapt to when designing SMS surveys, especially if you are used to writing questions for online or face-to-face interviews. With SMS, each question and corresponding answer choices must fit into 160 characters, the standard length of a text message. If the text is any longer, it will be split into multiple messages – while messaging services attempt to deliver these in the correct order, they can often come in incorrectly. An example of a question and answer text that fits into 160 characters is below. In order to achieve this, the question has been trimmed of unnecessary spaces, and the text kept as simple as possible while maintaining the integrity of the question:

• • In what types of stores do you shop for food and drink?
    1)Malls
    2)Retail shops
    3)Department Stores
    4)Supermarket
    5)Specialty Stores
    6)Discount Stores
    7)Other
    

To measure question length, you can use the =LEN formula in Excel – GeoPoll’s standard questionnaire template for SMS has this formula in a column to the right of every question. Using abbreviations or slang can also help remove unnecessary characters, though overuse of these terms is not recommended. Finally, if it proves impossible to fit all questions and answer options into 160 characters, you can break the message into two by placing the question in the first message and ending with a message such as “Press 1 to see answer options.” By breaking the messages within the survey design rather than risking them getting split on delivery, you can control how they appear to the survey respondent.

Design Short Questionnaires: In addition to making individual question length short, the overall questionnaire length should also be quite short. GeoPoll recommends that SMS surveys should take about 10-15 minutes to complete, which usually equates to about 30-40 questions, including any screener questions and demographic questions. By testing the survey both internally and with a pilot group of respondents, researchers can see if the drop-off rates for their survey are higher than expected and adjust before sending the survey to the full sample.

Use Clear Opt-in and Instructional Language: As with any survey, the first message should be an opt-in to that specific survey, even if the respondent has already opted-in to be part of a general pool of survey respondents. SMS surveys are no exception, and opt-in language should be clear around the survey length and provided incentive when applicable. Instructional language, such as text that says “Reply with a number” for a multiple-choice question, should also be clear and easy to understand.

Avoid Certain Types of Questions: A critical component of developing SMS questionnaires is understanding what question types they excel at versus those they do not support. Certain question types, such as matrix questions or those that include pictures or videos, are generally not supported by SMS. In addition, research has shown that select all that apply question types do not perform as well via SMS than via other modes such as web link, with respondents selecting fewer choices on average when answering via SMS. Single-choice, yes/no, and ranking questions are all excellent question types to use in an SMS survey. SMS also supports open-ended questions, though due to the character limit of a text message, responses may be shorter than seen with other modes.

Conduct SMS Surveys with GeoPoll

SMS surveys are useful in a wide variety of applications and should be considered for surveys that can be adapted to fit the above guidelines. By partnering with GeoPoll, you will get access to a team of experts in SMS survey design, along with unique platform features such as free-to-respondent messages sent through a short code, and the ability to immediately incentivize respondents upon survey completion. To talk to GeoPoll about conducting your own SMS survey, contact us today.