PerCent-A covers the following main topics:

1. Consultation Service
   To establish appropriate perimetric guidelines for all involved sites:
   • Definition of appropriate perimetric procedures and quality control parameters.
   • Development of criteria for detection and progression of scotoma.
   • Development of a Visual Field Analysis Protocol as supplement to the study protocol.
2. Certification Service
   To promote a high level of competency among the visual field technicians responsible for the concerning trial:
   • Setting up the protocol for visual field technician training and certification procedures.
   • Teaching and certifying the visual field technicians of participating study sites via teaching sessions or (optionally) via remote instructions/protocols.
   • Certification by tests.
3. Data Processing Service
   For Octopus 101, Octopus 900, Humphrey Field Analyzer (HFA II, at least software version A 10.2 or HFA IIi, at least software version C 3.2). Other devices on request.
   1. Data management
      • Easy data transfer via internet to a central server.
      • Status of visual field processing in the reading center can be checked by the client.
   2. Data quality control
      • immediate check of each visual field upload
      • immediate feedback to the concerning study sites
      • preliminary quality control reports
   3. Date storage
      • Secure data storage due to a GNU/Linux server
      • SSL-secured access to the webserver is provided by a user friendly interface based on modern web technologies (Ruby on Rails, HTML5, jQuery, Sass). In the background a MySQL database is used.
4. Data Analysis
   According to Visual Field Analysis Protocol for detection of scotoma occurrence and assessment of scotoma change:
   • Glaucoma staging systems (e.g. HAP, Mills, Aulhorn)
   • Detection and evaluation of pathology.
   • Evaluation of conversion from normal to pathological / vice versa or unchanged status.
   • Evaluation/confirmation of pathology.
   • Progression analysis (pointwise linear regression [PLR], event criteria, perimetric indices in cooperation with the client).
5. Reports
   According to the customer’s/sponsor’s order.