Sending interviewers to targeted locations requires specific distribution options within the software itself, all of which can be found within Nfield CAPI. Have you already heard about sampling points?

​Sampling points help you organize the fieldwork

In face to face interviewing, we refer to sampling points when talking about survey distribution. So what are sampling points?

From a technical perspective, sampling points are a way of categorizing interviews into certain groups (points). Categories could literally be anything: streets, areas, cities, or even experienced interviewers in one sampling point and less experienced interviewers in another.

In practice, sampling points are commonly used for a geographical distribution of interviews. The usage of sampling points helps you

• assure a geographical representativeness of the survey
• simplify the quota frame
• control the fieldwork and targets better.

Thanks to sampling points it’s easy to assign interviewers to interviews and control your fieldwork!

The geographical categorization helps to divide and manage the fieldwork and survey targets because interviewers may live in different areas or because you need to find respondents across a number of areas. 

For example, when working on an international project involving many countries (offices worldwide), one sampling point could be one country (one office) with many interviewers.

Or in another case, when working on a local project, the town could be divided into parts with each one assigned to a different interviewer as a sampling point.

Nfield CAPI offers various scenarios

The following examples are theoretical and meant to explain you the main differences.

1. Surveys without sampling points and without quota
Non-geographical distribution is defined and your interviewers can ask anybody and anywhere.

Typical situation: polls

Example 1 without quota and sampling points actually means no table at all.

2. Surveys without sampling points and with quota
Non-geographical distribution is defined by sampling points, but please note that a quota frame can still be used for geographical distinction. The fieldwork is controlled through the total target that is placed in the software.

Typical situation: the interviewers who live in different cities interview people who are randomly passing by

Example 2 with quota, but no sampling points

3. Surveys with sampling points and quota
Geographical locations with the targets as the sampling points (Amsterdam East, Amsterdam West, Amsterdam South) need to be uploaded first, and then a quota frame with sample characteristics (female, male) should be set up. The fieldwork should be controlled through sampling points, not the total target. The sum of the sampling points targets is your total target, but having the total in the software does not help you control the fieldwork better.

Typical situation:  a complex set-up used for international or national projects when a detailed distribution is needed

Example 3.1. with sampling points and quota, less items

Example 3.2. with sampling points and quota, more items

Face-to-face interviewing is a complex process comprising interviewers, mobile devices and software. A multitude of elements within this process can make a project prone to mistakes, leading to a delay in the delivery or even data loss. Outlined below are our essential tips for some of the most common problems associated with face-to-face interviewing to help you ensure a smooth execution of all CAPI projects.

1. Select the right device

The Nfield CAPI app runs on all Android tablets and smartphones, though not every device will serve you accordingly. We recommend that you run through a checklist mapping the factors that come into play when selecting the right CAPI device.

2. Embrace the issue of security

Security of your data is an absolute priority to us. Rest assured that we do our utmost to keep your data safe, however you also have a crucial role to play in data security by following a few simple rules:

• Ensure that you can wipe a device remotely in the event that it gets stolen. If this is not a feature on the device itself, please consider acquiring such a service. Mobile Device Management (MDM) software will help you configure, manage and secure mobile devices. Never heard before? Please see http://www.air-watch.com.
• Create logins per interviewer; never set up logins per device. Nfield CAPI enables you to track activities taken by the interviewers through their unique user ID.
• Set strong password requirements in Nfield CAPI, and ask your interviewers to keep their logins confidential or even to change the password regularly. The downside is that the more complex password, the bigger chance the interviewers will eventually jot it down on a piece of paper.
• Apply a user role configuration that defines a scale of activities the user is allowed to perform in Nfield CAPI. When somebody leaves the company, don’t forget to remove them from Nfield CAPI immediately.
• Once the quota of interviews for your project is reached and the fieldwork concludes, press the STOP button on the Nfield CAPI interface to automatically remove the survey from all devices the next time interviewers sync.
• Un-assign interviewers who no longer work on the project.

3. Prevent possible trouble in your fieldwork…

… by informing your interviewers thoroughly about how to use the Nfield app. 

• Always log out of the app at the end of the day – never remain signed in the Nfield CAPI app.
• Sync regularly so that you work with the latest version of the survey and its information. Please bear in mind that transferring large volumes of data after various days of work may take you plenty of time.
• Ensure your internet connection is stable when you start syncing the data, and do not change your network connection as this can disrupt the data transfer.

• Activate the GPS on your mobile device if you receive a notification through the Nfield CAPI app.
• If you are assigned to a project which includes addresses and you share the device with more interviewers, don’t leave unfinished interviews in the Nfield CAPI app. When the next interviewer logs in and syncs his data on the device, your unfinished interviews will be removed.
• Use the device’s energy source wisely as you will be using it throughout the day to complete all interviews. Please see the recommendations how to prolong battery life.

4. Monitor updates

There are two types of software updates that you need to be aware of:

1. Nfield CAPI app updates
2. Android operating system updates

Nfield CAPI app updates (NIPO)

The Nfield CAPI app is managed by NIPO, and any updates are designed solely to augment the features of the app. Every release automatically updates the backend of Nfield CAPI but requires the manual intervention of the interviewer to take effect on the device.

Android operating system updates (Google)
All Android operating system updates are managed by a third party – Google. These updates impact the software that the whole device runs on; they are not primarily calibrated to Nfield CAPI functionality.

The Android operating system update usually starts by a window which automatically opens on the screen asking for permission to update the operating system.  The interviewer will need to consent to this before any updates can take place. In other words, the update doesn’t happen automatically.

Whilst we thoroughly test all major updates of the Android operating system to examine whether Nfield CAPI features have not been affected, due to the diversity of mobile devices available and the number of versions of the Android operating being used at any one time, it makes in-depth testing on a large scale impossible.

5. Consider training options

Experienced researchers and fieldwork executives dive into Nfield CAPI without any hurdles. The same applies to scripters who are already familiar with the ODIN language. For those users who require full scale onboarding, we offer introductory and tailored training.

Quality control is a process when fieldwork executives look into various source files to evaluate whether the interviews have been conducted with honesty and accuracy. It is in the researchers’ best interests to ensure that the data delivered to customers comply with the highest quality standards.

Nfield CAPI for smart quality control

In Nfield CAPI you can use location tracking and silent recording with ease to verify data and the credibility of your interviewers.

Silent recording enables you to record either the whole interview or parts of it without the interviewer’s knowledge. It is set up via scripting by inserting a simple command.

Location tracking means collecting unbiased information about the locations where your interviews have been conducted. To allocate an interviewer, the device has to be equipped with:

• the GPS receiver which is the most popular and more accurate option and/or
• Wi-Fi and mobile network – GSM, 3G or 4G which, on average, provides less accuracy than the GPS.

Things to remember about GPS

• The interviewer can activate both the GPS and Wi-Fi and mobile network options in device settings, and let the system decide which one will capture the location best given the current conditions. It is very convenient, though activating both options consumes battery life very quickly.
• How accurately the GPS is able to capture a location depends on various factors: number of satellites in view, mountains and ionospheric disturbances, signal interference caused by buildings and number of channels on the receiver. Specifications for most GPS receivers indicate their accuracy will be within 5-15 meters, 95% of the time. This assumes the receiver has a clear view of the sky and has finished acquiring more than three satellites. If the conditions are not ideal then the accuracy declines rapidly.
• Nfield CAPI automatically attempts to capture the current location of an interviewer when the survey is started. This process happens discreetly in the background and without interviewer intervention. If the required accuracy is not achieved, the interviewer will need to confirm the best available location match manually after completing the interview. The location is saved in paradata and only persons with assigned rights are permitted to download this to view the locations of the interviews.

More options: measure twice, cut just once

In addition to the aforementioned methods, you can utilize Nfield CAPI for:

• Speeding – measure the average time needed to take the survey and check if some interviews have been completed way faster than is realistically possible. You can download the interview duration easily.
• Straightening – analyze the data to see if the same answer category for a series of questions appears too frequently.
• Pictures – look into the data and view the pictures snapped during the interviews.
• Call back – use the gathered contact information of respondents to conduct random calls to verify the data.

You can reject interviews that do not meet the quality standards in Nfield CAPI which will then  eliminate them from the complete target counts and exclude their data from the overall survey data.

Care about the best quality for your customers

False or insincere interviews provide useless data that cannot be delivered to customers, nor do they support the researchers’ objectives. The situation can even tarnish your reputation if the wrong data is used for expensive, important analyses that influence customers’ business decisions. Whilst the majority of interviewers respect their job and the nature of their work, there will always be a small percentage who will try and find shortcuts.
 
A lack of quality control usually results in more cases of false interviews. Pen and Paper researchers struggle with quality the most. Based on our experience, a few dishonest interviewers are revealed at the start when switching from Pen and Paper to CAPI, and as soon as the interviewers realize that the quality of their work is being thoroughly checked, the number of unfortunate incidents decline. Further features of the quality control system then prevents a come-back of dishonest practices.

In this Academy session we explain the files Nfield uses and generates, along with all the possibilities. We elaborate on the relation of the U-file and O-file with the script. More details are shared about the paradata, all the information in there and how that could be used. Finally, we will discuss the media files.

Performance of the Nfield CAPI app (most often shown by speed of screen refresh) is critical. We share some guidelines on what to do and what to avoid when creating an Nfield CAPI ODIN script.

A webinar about working with the NIPO DSC for IBM SPSS. With the NIPO DSC you can open NIPO Software data directly in SPSS. There is no need to convert the data. With the NIPO DSC you can run your data processing and analytical processes completely in IBM SPSS, even though the data is collected using NIPO Software’s technology.

Learn the basics on how to theme the NfieldChicago template.

Introduction to the ODIN syntax and new features of the NfieldChicago template.