Category: Data Management Level: Beginner Reading time: 10 minutes Updated: 2025-10-31

Managing and Downloading Data

Quick Summary: View participant progress, browse test results, and download data files for analysis.

What You'll Learn

  • Accessing your study data
  • Understanding data file formats
  • Downloading data for analysis
  • Viewing participant progress
  • Managing data storage

Overview

The PEBL Online Platform automatically collects and stores data as participants complete tests. You can view summary statistics, monitor progress, and download complete datasets for statistical analysis.

Step-by-Step Guide

Step 1: Access Browse Data

From the main menu, click Browse Data

This shows:

  • All your active studies
  • Participant counts
  • Completion statistics
  • Quick access to data downloads

Step 2: Select Your Study

  1. Find your study in the list
  2. Click on the study name to view details
You'll see:
  • Study information: Name, token, dates
  • Overall statistics: Total participants, completion rate
  • Test/Chain list: Each test with participant counts
  • Recent activity: Latest submissions

Step 3: View Participant Progress

The participant list shows:

  • Participant ID: How each participant is identified
  • Status: Complete, In Progress, or Abandoned
  • Progress: Percentage complete (for chains)
  • Last activity: Most recent data submission
  • Actions: View details, download individual data

Status meanings:

  • Complete: All tests/items finished
  • In Progress: Started but not finished
  • 📍 Active Now: Activity within last hour
  • Likely Abandoned: No activity for several days

Step 4: Download Data

Option A: Download All Data (Recommended)

  1. Click Download All Data button
  2. Receives a ZIP file containing:
  • One CSV file per test
    • Summary statistics
    • Metadata (timestamps, parameters used)
    • README file explaining file structure

Option B: Download Individual Test Data

  1. Find the test in the test list
  2. Click Download next to that test
  3. Receives CSV file for that specific test only

Option C: Download Individual Participant Data

  1. Find participant in participant list
  2. Click View Details
  3. Click Download for specific data files
  4. Useful for checking individual participant submissions

Understanding Data Files

File Structure

Downloaded ZIP contains:

STUDY<em>ABC123</em>data<em>2025-10-31/

├── README.txt # File descriptions ├── study</em>metadata.json # Study configuration ├── corsi<em>summary.csv # Summary scores per participant ├── corsi</em>trials.csv # Trial-by-trial data ├── stroop<em>summary.csv # Summary scores ├── stroop</em>trials.csv # Trial-by-trial data

└── ...

CSV File Formats

Summary Files

One row per participant:

participant<em>id,score,correct</em>trials,reaction<em>time</em>mean,completion<em>time

SUBJ001,85,42,850,1234567890

SUBJ002,92,46,720,1234568901

Common columns:

  • participantid: Unique participant identifier
  • score: Overall performance score
  • correcttrials: Number of correct responses
  • reactiontimemean: Average RT in milliseconds
  • completiontime: Unix timestamp when completed

Trial-by-Trial Files

One row per trial:

participant<em>id,trial,stimulus,response,correct,reaction</em>time,timestamp

SUBJ001,1,LEFT,LEFT,1,645,1234567890 SUBJ001,2,RIGHT,LEFT,0,823,1234567891

SUBJ001,3,LEFT,LEFT,1,602,1234567892

Common columns:

  • participantid: Unique identifier
  • trial: Trial number (1, 2, 3...)
  • stimulus: What was presented
  • response: Participant's response
  • correct: 1 = correct, 0 = incorrect
  • reactiontime: RT in milliseconds
  • timestamp: When trial occurred

Metadata Files

studymetadata.json

Contains:

{

"study</em>name": "Spatial Memory Study", "token": "STUDY<em>ABC123", "created": "2025-10-15", "tests": ["corsi", "stroop", "tower-of-london"], "parameters": { "corsi": { "isi": 1200, "dopractice": 0 } }

}

Useful for documenting:

  • Which parameter values were used
  • Study configuration
  • Data collection dates

Data Analysis Workflows

Workflow 1: R Analysis

<h1>Load data</h1>

library(tidyverse)

<h1>Read summary data</h1> corsi <- read</em>csv("corsi<em>summary.csv") stroop <- read</em>csv("stroop<em>summary.csv")

<h1>Merge datasets</h1> data <- corsi %>% inner</em>join(stroop, by = "participant<em>id")

<h1>Analyze</h1> summary(data)

cor.test(data$corsi</em>score, data$stroop<em>score)

Workflow 2: Python Analysis

import pandas as pd

import numpy as np

<h1>Load data</h1> corsi = pd.read</em>csv("corsi<em>summary.csv") stroop = pd.read</em>csv("stroop<em>summary.csv")

<h1>Merge</h1> data = pd.merge(corsi, stroop, on="participant</em>id")

<h1>Analyze</h1> data.describe()

data[['corsi<em>score', 'stroop</em>score']].corr()

Workflow 3: SPSS/Excel

  1. Download ZIP and extract
  2. Open summary CSV files in Excel or SPSS
  3. Each test is a separate file
  4. Merge by participantid column if analyzing multiple tests

Storage Management

Understanding Storage Quotas

Each subscription tier has a storage limit:

TierStorage Limit
Free500 MB
Student2 GB
Researcher10 GB
Research Plus25 GB
Institutional100+ GB

Checking Storage Usage

  1. Go to Account Settings or Dashboard
  2. View Storage Used meter
  3. Shows: Used / Total (e.g., "2.3 GB / 10 GB")

Managing Storage

If approaching limit:

  1. Download and delete old studies:
  • Download data for completed studies
    • Archive ZIP files on your computer/server
    • Delete study from platform to free space
  1. Clean up abandoned sessions:
  • Remove data from participants who never completed
    • Use "Delete participant" function carefully
  1. Compress data (automatic):
  • Platform automatically compresses old data
    • Recent data: uncompressed for fast access
    • Old data: compressed to save space
  1. Upgrade tier:
  • Contact administrator about upgrading
    • Higher tiers have more storage

Important: Always download data before deleting studies!

Study Analytics

Accessing Analytics

  1. Go to My Research Studies
  2. Click Analytics next to your study
Or:
  1. In Browse Data, select your study
  2. Analytics shown automatically

Key Metrics

Recruitment:

  • Total participants started
  • Completion rate
  • Average time to complete
  • Dropout points (where participants stopped)

Progress (for chains):

  • Items completed distribution
  • Current item for in-progress participants
  • Sticking points (items with high abandonment)

Data Quality:

  • Missing data counts
  • Error rates
  • Upload failures

Using Analytics

Monitor recruitment:

  • Track progress toward sample size goal
  • Identify if recruitment is too slow
  • Plan when to close study

Identify problems:

  • High abandonment at specific test → too difficult or buggy
  • Many upload failures → technical issue
  • Long average times → tests too long or confusing

Optimize:

  • Adjust parameters if tests too hard/easy
  • Shorten battery if completion rate low
  • Fix technical issues causing abandonment

Common Tasks

Export for Publication

  1. Download all data
  2. Create analysis scripts (R, Python, SPSS)
  3. Generate summary statistics
  4. Document:
  • Parameter values used
    • Data collection dates
    • Any exclusions/preprocessing
    • Sample characteristics

Share Data with Collaborators

Option 1: Download and share files

  1. Download ZIP
  2. Share via secure file transfer (email, cloud storage)
  3. Include README explaining file structure
Option 2: Grant collaborator access
  1. Go to Study Settings
  2. Add collaborator username
  3. They can access data directly through platform

Merge Data from Multiple Studies

If running same test across multiple studies:

<h1>R example</h1>

study1 <- read</em>csv("study1/corsi<em>summary.csv") %>% mutate(study = "study1")

study2 <- read</em>csv("study2/corsi<em>summary.csv") %>% mutate(study = "study2")

combined <- bind</em>rows(study1, study2)

Include study variable to track data source.

Identify and Handle Missing Data

<h1>Python example</h1>

import pandas as pd

data = pd.read<em>csv("corsi</em>summary.csv")

<h1>Check for missing</h1> print(data.isnull().sum())

<h1>Remove participants with missing critical data</h1> data<em>clean = data.dropna(subset=['score', 'reaction</em>time<em>mean'])

<h1>Or fill with mean/median</h1>

data</em>filled = data.fillna(data.mean())

Best Practices

1. Download Data Regularly

Don't wait until study ends:

  • Download weekly or monthly during data collection
  • Acts as backup if technical issues occur
  • Allows ongoing analysis and quality checks

2. Version Control

Keep organized archives:

MyStudy/

├── data<em>2025-10-15</em>pilot/ ├── data<em>2025-10-31</em>main<em>n50/ ├── data</em>2025-11-15<em>main</em>n100/

└── data<em>2025-11-30</em>final/

Document what each version contains.

3. Check Data Quality Early

After first 5-10 participants:

  • Verify data files look correct
  • Check for obvious errors
  • Test your analysis scripts
  • Catch issues before collecting full sample

4. Document Parameters

Save study metadata:

  • Which parameter values were used
  • Any changes made mid-study
  • Reasons for changes

This is crucial for methods sections and replication.

5. Exclude Systematically

Document exclusion criteria:

  • How you define incomplete data
  • RT outlier criteria
  • Performance-based exclusions
  • Apply consistently

6. Protect Participant Privacy

  • Keep data files secure (encrypted storage)
  • Remove identifying information if needed
  • Follow IRB/ethics requirements
  • Don't share raw data publicly without permission

Troubleshooting

Data Not Appearing

Causes:

  • Participant hasn't completed test yet
  • Upload failed (network issue)
  • Wrong study token
  • Browser blocked upload

Solutions:

  1. Wait for participant to complete
  2. Check participant's browser console for errors
  3. Verify study token correct
  4. Ask participant to retry with stable internet

Downloaded File Won't Open

Causes:

  • ZIP file corrupted during download
  • No program to open CSV files
  • File encoding issue

Solutions:

  1. Re-download the file
  2. Use Excel, R, Python, or text editor for CSV
  3. Check file encoding (should be UTF-8)

Missing Participant Data

Causes:

  • Participant started but didn't finish
  • Uploaded to wrong study token
  • Data filtered by date range

Solutions:

  1. Check if participant status is "In Progress"
  2. Verify they completed all tests in chain
  3. Check correct study selected
  4. Look in other studies (if using multiple)

Data Doesn't Match Expectations

Causes:

  • Wrong parameter configuration
  • Test version mismatch
  • Participant misunderstood instructions

Solutions:

  1. Check study_metadata.json for parameter values
  2. Review test version used
  3. Check first few participants' data carefully
  4. Consider pilot testing before main study

Related Topics


Need more help? Contact your platform administrator or refer to test-specific documentation for details about particular data file formats.


Related Topics